vFabric GemFire Tools - VMware Documentationpubs.vmware.com/.../PDF/vfabric-gemfire-tools-ug-6.6.4.pdf2009/01/19 · vFabric GemFire Tools VMware vFabric GemFire GFMon 2.7 VMware vFabric

vFabric GemFire ToolsVMware vFabric GemFire GFMon 2.7

VMware vFabric GemFire Data Browser 1.4

VMware vFabric GemFire VSD

VMware vFabric GemFire 6.6

VMware vFabric Suite 5.2

VMware vFabric Suite 5.1

VMware vFabric Cloud Application Platform 5.0

This document supports the version of each product listed andsupports all subsequent versions until the document is replaced bya new edition. To check for more recent editions of this document,see http://www.vmware.com/support/pubs.

EN-000672-00

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VMware, Inc.3401 Hillview Ave.Palo Alto, CA 94304

Contents

About vFabric GemFire Tools........................................................................................5Technical Support...........................................................................................................7

Chapter 1: GFMon.......................................................................................9GFMon Overview..........................................................................................................................................9GFMon System Requirements...................................................................................................................10Installing and Uninstalling GFMon..............................................................................................................11Running the Agent and GFMon..................................................................................................................13Monitoring the GemFire Distributed System Using GFMon........................................................................14

Chapter 2: DataBrowser...........................................................................31DataBrowser Overview...............................................................................................................................31DataBrowser System Requirements...........................................................................................................31Installation and Licensing...........................................................................................................................31Running DataBrowser.................................................................................................................................32Connecting DataBrowser to a vFabric GemFire System............................................................................33Tour of DataBrowser...................................................................................................................................34DataBrowser Preferences...........................................................................................................................37How DataBrowser Works............................................................................................................................39

Chapter 3: Visual Statistics Display........................................................43VSD Overview.............................................................................................................................................43VSD System Requirements........................................................................................................................45Installing and Running VSD........................................................................................................................46Viewing Statistics in VSD............................................................................................................................47

Glossary........................................................................................................................51

iii

About vFabric GemFire Tools

vFabric GemFire Tools provides information for installing and using the optional tools available for the VMware®

vFabric™ GemFire® data management system. These tools are in addition to the tools that are included in theGemFire product. vFabric GemFire and its associated tools are also part of the VMware® vFabric Suite™.

Intended Audience

vFabric GemFire Tools is intended for anyone who is familiar with vFabric GemFire and wants to use theoptional GemFire tools described in the document.

5

Technical Support

VMware provides several sources for product information and support. The vFabric GemFire User's Guide, thevFabric GemFire Native Client User's Guide, the vFabric GemFire Tools Guide and the online API documentationsets should always be your first source of information. VMware technical support engineers will refer you tothese documents when applicable. However, you may need to contact technical support for the following reasons:

• Your technical question is not answered in the documentation.• You receive an error message that directs you to contact technical support.• You want to report a bug.• You want to submit a feature request.

For questions concerning product availability, pricing, license serial numbers, or future features, contact youraccount manager.

Preserving Artifacts for Technical Support

If you have a hung application and you do not have to kill it, leave it while you contact technical support. If youcannot leave the application running, and it is running under Unix, signal it twice with this command, lettingfive to ten seconds pass between the two signals:

kill -QUIT pid

This will send the application’s stack dumps into the log file for inspection. For Windows systems, call TechnicalSupport for assistance in obtaining stack dumps.

Don’t delete any files until you call technical support and find out exactly what data may be useful to supportor engineering. Save all the artifacts, including:

• Log files. Send the full log to technical support, not just the stack. Even at the default logging level, the logcontains data that may be important, such as the operating system and license information.

• Statistics archive files.• Core files.• For Linux, you can use gdb to extract a stack from a core file. Call Technical Support if you need assistance.• Crash dumps.• For Windows, save the Dr. Watson output.

Contacting Technical Support

The VMware support sites at https://www.vmware.com/support/contacts/ andhttps://www.vmware.com/support/policies/howto.html provide all the information you need to contact ourtechnical support team. To file a support request, use the VMware technical support request site athttp://www.vmware.com/srfile/. Note that you will need a valid VMware support profile account to be able tologin and file the support request. You can also use the system to view your active support contract levels. Ifyou are unable to access the website for any reason, you can call technical support (U.S. English/Toll Free) at1-877-486-9273.

When contacting VMware technical support, please be prepared to provide this information:

• Your name, company name, and GemFire license numbers• The GemFire product and version you are using• The hardware platform and operating system you are using• A description of the problem or request• Exact error messages received, if any

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https://www.vmware.com/support/contacts/

https://www.vmware.com/support/policies/howto.html

http://www.vmware.com/srfile/

• Any artifacts you are able to gather

Your product support agreement may identify specific individuals who are responsible for submitting all supportrequests. If so, please submit your information through those individuals. All responses will be sent to authorizedcontacts only.

24x7 Emergency Technical Support

VMware offers, at an additional charge, 24x7 emergency technical support. This support entitles customers tocontact us 24 hours a day, 7 days a week, 365 days a year, if they encounter problems that cause their productionapplication to go down, or that have the potential to bring their production application down. Contact youraccount manager for more details.

Training and Consulting

Consulting and training for all GemFire products are available through VMware’s professional servicesorganization.

Training courses are offered periodically at VMware’s offices in Beaverton, Oregon, or you can arrange foronsite training at your desired location.

Customized consulting services can help you make the best use of our products in your business environment.

Contact your account representative for more details or to obtain consulting services.

vFabric GemFire Tools8

Chapter 1GFMon

The GFMon tool monitors a vFabric GemFire system in real time. It provides health information, detailed operationaland configuration data, system alerts, throughput performance, and statistics for system members and connected clients.

GFMon OverviewGFMon is a graphical monitoring tool that allows you to view useful information about the state of a runningvFabric GemFire system.

A GemFire distributed system is a collection of cache servers and data stores that provide consistent access tostored data. A typical GemFire deployment consists of a combination of processes:

• Cache servers/data stores• System member locators• Clients• WAN gateways

For more information about GemFire, see the GemFire User's Guide.

Each process in the distributed system consumes resources like CPU, memory, disk and bandwidth and providesthe ability to access and manipulate data that is stored in the distributed system cluster.

Each data store is comprised of multiple data regions. Regions can be replicated or partitioned. Applications canperform a wide variety of operations on the data, ranging from map-like data access and update to running queriesand transactions on the data. The distributed system maintains group membership information, and also storesstatistics about every relevant aspect of the system. Each member can be configured to write out its statistics toa pre-configured file. These files can be inspected using GemFire tools for offline inspection of the data.

Note: Every statistic that is written by GemFire is also available as a JMX MBean.

GemFire provides an agent process that can be started in each system. The agent, which is an MBean server,provides JMX access to important statistical runtime information about the system. The agent supports HTTPand RMI adaptors. You can use JMX at run time to mine the statistics you need to monitor. Many GemFirecustomers choose to directly interface with the agent process.

GFMon is a graphical monitoring tool that allows you to easily view useful pertinent information about the stateof the running system at any moment. GFMon runs as a JMX client that connects to the agent process, retrievesrelevant statistics, and presents them to the end user. GFMon uses the same API that any JMX client would useto collect information about the GemFire system. GFMon does not make use of the GemFire Health MBeans.

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By providing a summary of all the relevant statistics in the system, GFMon gives the end user a bird's eye viewof the overall health of the system. For example, severe and warning messages written to the GemFire log areautomatically converted to JMX strings and are displayed in GFMon. These alerts would indicate problems inthe operating environment of one or more system members, prompting you to take action.

GFMon System RequirementsVerify that your system meets the installation and runtime requirements for GFMon.

GFMon is designed to run with full capabilities on platforms running Linux and Microsoft® Windows®.

Supported Platforms

This table lists the operating system and JDK/JRE combinations that GFMon supports. If you are interested ina platform that is not listed, please contact your VMware sales representative. VMware will evaluate whether itcan support the platform, either as-is or under a special agreement, or whether there are reasons that preventdeploying on a particular platform.

Sun JSE 1.6.0_23Sun® JSE 1.6.0_17Operating System

XRed Hat® Enterprise Linux® 5 (patch 3),

kernel version 2.6.18-128 EL, with GTK

2.10.4-20.el5

XWindows XP 32-bit SP3

XWindows XP 64-bit SP2

XMicrosoft Windows Server® 2003 SP2

These sections list the operating systems used for building and testing GFMon. GFMon may work with latersystem releases upon which it has not been tested.

Windows

GFMon has been tested successfully on:

• Windows XP 32-bit SP3• Windows XP 64-bit SP2• Windows Server 2003 SP2

Linux

GFMon has been tested successfully on:

• Red Hat Enterprise Linux 4 (patch 7), kernel version 2.6.9-78 EL• Red Hat Enterprise Linux 5 (patch 3), kernel version 2.6.18-128 EL

If you are not sure of the kernel version on your system, use this command to list it:

prompt> uname -r

Java Runtime Requirements

You must have a Java Runtime Environment (JRE) 1.5.0 or later for GFMon to run. GFMon does not include abundled JRE or JDK so you can choose the version that best suits your unique system requirements. Note that


the JDK/JREs versions listed in "Supported Platforms" above are the versions that were used during producttesting. You can download the appropriate JDK or JRE from http://java.sun.com.

Runtime Requirements

GFMon has these additional runtime requirements:

• Intel® 2 GHz Pentium® 4 (or equivalent) proessor• 1 GB RAM (recommended)• JMX admin agent running in GemFire 5.7 or higher

Other Software Requirements

You need Adobe Acrobat Reader for viewing the documentation distributed as PDF files. Download a free copyat http://www.adobe.com/products/acrobat/readstep.html.

You need a web browser to launch the documentation index page from the GFMon Help menu.

Installing and Uninstalling GFMonInstall GFMon to the location of your choice and customize your environment settings as needed to run GFMon.

To obtain GFMon, go to the VMware download center at http://downloads.vmware.com/d/. Navigate to thevFabric GemFire download page, under the Drivers & Tools tab.

Installation Procedure

1. The GFMon installation program is distributed as an executable JAR file. Ensure that the path to a supportedversion of the Java executable is in your PATH environment variable:

java -version

2. Change to the directory where you downloaded the GFMon software, and execute the JAR file installer. Onthe command line, type the following command for your operating system:

• UNIX and Linux (Bourne and Korn shells - sh, ksh, bash)

java -jar vFabric_GFMonXX_Installer.jar

where XX corresponds to the version of GFMon that you are installing.• Windows:

java.exe -jar vFabric_GFMonXX_Installer.jar

where XX corresponds to the version of GFMon that you are installing.

3. When the License Agreement (EULA) is displayed, press Enter to scroll and read. Enter agree to accept thelicense.

4. At the prompt, enter the full path of the directory in which you will install GFMon.

By default, GFMon is installed in the directory where you executed the JAR file.

5. Enter yes to create the directory if necessary, or to verify that the installation directory is correct.

The installer copies the license agreement and installs GemFire to a top-level GemFire directory in the locationyou specified.

Note: If you have difficulties getting the installer to work correctly, you can unzip the jar file directlywith any common zip extraction tool.

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GFMon

http://java.sun.com

http://www.adobe.com/products/acrobat/readstep.html

http://downloads.vmware.com/d/

The gfmon.bat and gfmon files are created in the location where you extract the JAR file. Use these files torun GFMon on Microsoft Windows and Linux, respectively.

Note: By default, gfmon.bat and gfmon use the environment variable java to point to the JDKversion that is available in the system. If you want to execute GFMon using a specific version of JDK,you can specify the location of the Java executable file using the environment variable GF_JAVA.

You do not need a special GFMon license to run GFMon. GFMon uses your GemFire licensing when you runit with the JMX admin agent.

Uninstall GFMon by deleting the GFMon product tree.

Setting Environment Variables

Set the environment variable GEMFIRE to point to the GemFire product directory. This directory must be thesame as the GemFire product directory that is being used by the JMX admin agent that GFMon connects tomonitor the distributed system. The GFMon start-up scripts launch GFMon using the gemfire.jar in theGemFire product lib directory.

To use a specific JVM, set the environment variable GF_JAVA to the required JVM binary. For example, onWindows platforms, execute the following command:

set GF_JAVA=C:\jdk1.5.0\bin\java.exe

On Linux platforms, execute:

export GF_JAVA=/jdk1.5.0/bin/java

To specify JVM arguments, use the environment variable JAVA_ARGS. Windows example:

set JAVA_ARGS=-Xms256m

Linux example:

export JAVA_ARGS=-Xms256m

To specify multiple arguments or arguments with equal-to (=), use double quotes (""). Windows example:

set JAVA_ARGS="-Xms256m -Xmx512m"

Linux example:

export JAVA_ARGS="-Xms256m -Xmx512m"

To specify the SSL configuration of GFMon when the JMX Agent has SSL enabled, use the environment variableJAVA_ARGS. Windows example:

set JAVA_ARGS="-Djavax.net.ssl.keyStoreType=jks -Djavax.net.ssl.keyStore=/path/to/trusted.keystore-Djavax.net.ssl.keyStorePassword=password-Djavax.net.ssl.trustStore=/path/to/trusted.keystore-Djavax.net.ssl.trustStorePassword=password"

Linux example:

export JAVA_ARGS="-Djavax.net.ssl.keyStoreType=jks -Djavax.net.ssl.keyStore=/path/to/trusted.keystore-Djavax.net.ssl.keyStorePassword=password-Djavax.net.ssl.trustStore=/path/to/trusted.keystore-Djavax.net.ssl.trustStorePassword=password"


Running the Agent and GFMonConfigure and run your GemFire JMX Agent and the GFMon tool. Use GFMon to connect to the agent andretrieve information about the running GemFire system.

GFMon requires a GemFire distributed system with a running Admin Java Management Extensions (JMX)Agent with RMI enabled. These steps take you through GemFire configuration and startup at a high level. Fordetailed information on GemFire system configuration and on running a GemFire system and a GemFire JMXagent, see the GemFire User's Guide.

The instructions that follow require a running GemFire distributed system. You need to know how systemmember discovery is configured in the system. If you are not sure how your system is being run, see the sectionon Topology and Communication in the GemFire User's Guide

Configuring and Starting a JMX Agent

Start a JMX Admin Agent in the distributed system you want to monitor with GFMon. For information on howto configure a JMX Admin Agent, see the information on using JMX in the GemFire User's Guide.

1. Start the agent, specifying the RMI listen port and RMI-enabled parameter as part of the start-up argumentsor as part of the agent.properties file. Example:

agent start rmi-enabled=true rmi-port=1099

Note: The Agent uses a default port of 1099 to listen for incoming RMI connections from JMX clients,including GFMon. If you specify an RMI-port that is not available, the JMX Agent reports an errorduring start-up.

2. Verify the RMI-port value from the agent.log file, which is created when the agent starts. You can alsolist the active connections using the command: netstat-a.

3. Record the agent host-name and the RMI-port number from the agent.log file.

After you start the GemFire JMX Agent in the GemFire distributed system, you can use the agent host nameand the RMI port to connect GFMon to the system.

Starting an Admin Agent with a Non-Default Statistics Refresh Interval

GemFire refreshes statistic resources periodically and propagates these values to the JMX Admin Agent. GFMongets updated values of these statistics from the admin agent. If your admin agent connects to a system runningGemFire version 6.0 or more, you can optionally set this refresh-interval (specified in seconds) while startingthe agent. For systems running GemFire version 6.6.2 or earlier, the default value for refresh-interval is 5 seconds.For systems running GemFire version 6.6.3, the default value for refresh-interval is 15 seconds. The followingcommand changes it to 3 seconds:

agent start rmi-enabled=true rmi-port=1099 refresh-interval=3

Starting an Admin Agent Using Locators

To start the agent in a system using locators for member discovery, specify the connection string of the locator.This can be a comma-delimited host[port] list specified in the agent.properties file or on the commandline as part of the start-up arguments. Example:

agent start locators=bishop[10334] mcast-port=0

When you use locators, set the mcast-port to 0.

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GFMon

Starting an Admin Agent Using Multicast

To start the agent in a system using multicast for member discovery, specify the mcast-port for the system.This can be specified in the agent.properties file or on the command line as part of the start-up arguments.Example:

agent start mcast-port=10334

Starting GFMon and Connecting to the JMX Agent

To start GFMon:

1. Set the environment variable GEMFIRE to the GemFire product directory. This must be the same as theGemFire product directory that is being used by the admin agent GFMon is going to connect to. The GFMonstart-up scripts use the gemfire.jar in the lib subdirectory of GEMFIRE directory to launch GFMon.

2. Launch GFMon by running gfmon.bat on Windows platforms and gfmon on Linux platforms.3. In GFMon's Quick Connect section, enter the host name of the host on which the JMX Admin Agent is

running, and the RMI-port number for the agent.4. Click Connect to create the connection.

Running Multiple Instances of GFMon

You can run multiple instances of GFMon by invoking the GFMon script multiple times.

Disconnecting from the Admin Agent

To disconnect from an agent, click Disconnect on the left panel of the user interface.

Monitoring the GemFire Distributed System Using GFMonUse GFMon to monitor GemFire system health, alerts, and other information.

GFMon allows you to manage and monitor a GemFire distributed system in real-time. You can view the followinginformation:

• Overall health indicators of the distributed system• Overall system information• Information on various configurational aspects of the distributed system• Aggregate and detailed information on various operational aspects of the distributed system• System alerts that allow you to take the appropriate corrective action• Summary of alerts that have occurred across the distributed system

GFMon also provides the following features:

• A rich graphical user interface (GUI) with information on memory and CPU usage across the servers in thedistributed system

• Ability to create custom alerts by specifying system statistic thresholds

GFMon uses JMX to retrieve information from the distributed system. GFMon does not use the GemFire HealthMBeans.

Left Panel

The left panel helps you to navigate through various sections of the GFMon tool.


• Click the specific option in the GFMon section to navigate across the various information panels.• Use the Quick Connect section to specify the Agent Host and the Agent Port to which the connection must be

established. If the agent host name is not compliant with RFC 952 as mandated by RMI, GFMon fails to connectto the agent. After entering the host name, click Connect to connect to the distributed system. After connectingto the distributed system, the label for Connect button changes to Disconnect. To disconnect from the distributedsystem, click Disconnect.

Note: When you disconnect from the agent in GFMon or if the JMX agent shuts down, the data in thepanels is not cleared. When you connect to any distributed system again, the panels are cleared andpopulated with the new data.

• The System Status section displays the state of the distributed system to which you are connected. The followingcolors are displayed:

• Green. The system is functioning normally• Yellow. User-defined statistic alerts are raised and/or system alerts with severity Warning are raised.• Red. System alerts with severity Error or Severe are raised and/or a member has crashed.

To reset the GFMon System Status indicator, click Reset State. For more information, point the mouse-pointerat any lights displayed in the System Status section.

Tool-tip: When you place the mouse pointer over various GFMon user interface (UI) elements, tool-tips appearand provide to you additional information about the specific UI element.

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GFMon

Summary Panel

The top-most section in the Overview, Data, Members, or Alerts panel displays the host and port of the JMXadmin agent to which GFMon is connected or disconnected.The number of servers, gateways, and clients in thedistributed system are also displayed in this summary panel.

Overview Panel

The Overview panel provides the aggregated system health information of all members in the distributed system,the agent that you are connected to, summary view of alerts from all members in the distributed system, andbasic member information.


• Alerts! The Alerts! table displays a summary of alerts triggered by events occurring in the distributed system.The table displays both System alerts and the Statistics alerts defined by the user. To clear an alert in the Alerts!section, right-click and select Clear. Double click on any of the alerts in the Overview Panel-> Alerts! orMember Panel-> Member Alerts Viewer to see more information about the alerts. The following pop-upwindows are displayed.

• System Alert pop-up. When you double-click on a system alert, a pop-up window including the followinginformation is displayed:

• Member Names. The names of the members for which the system alert has been raised.• First Time. The time at which the alert was raised for the first time.• Last Time. The time at which the alert was raised for the last time.• Severity. Displays the severity of the alert. Severity can be either Warning, Error, or Severe.• Detail Message. The detail log message for the alert.

System alerts include log entries that are tagged as Severe, Error, or Warning. System alerts also consist ofalerts indicating unexpected disconnection of a member from the distributed system, unexpected disconnectionof the JMX admin agent, and errors occurring in GFMon.

• Statistics Alerts Pop-up. When you double-click on a statistic alert, a pop-up window including the followinginformation is displayed:

• Member Name. The name of the member for which the alert has been raised.• First Time. The time at which the alert was raised for the first time.• Last Time. The time at which the alert was raised for the last time.• Count. The number of times this alert has been raised.• Statistic Name. The names of different statistics selected for that alert definition.• Last Value. The value for the statistic when the alert was raised for the last time.• Mean Value. This is the mean value for the statistic; it is calculated by taking the sum of values for each alert

divided by the count for the alert.• Range. Provides the minimum and maximum value for the statistic in the given time (First time and Last

time).

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GFMon

• Information Alert. When you double-click on an information alert, distinguished by red color, a pop-upwindow including the following information is displayed:

• Member name - The name of the member for which this alert has been raised, if applicable.• Alert Time - The date and time of the alert.• Severity - Level of severity of the alert.• Detail Message – The information alert message in detail.

Alerts are aggregated, that is, the event triggering the alert is shown as a single entry with updates only in theLast Raised Time column. Distinct Statistic alerts defined by the user are aggregated for each member. Systemalerts are aggregated across the members by the type of event that triggers the alert. The color in the SystemStatus section in the Left Panel changes to yellow or red on occurrence of alerts.

You may reset this to green to acknowledge that the alerts have been examined. On reset, the aggregation ofthe existing alert entries in the table is stopped and they are greyed out. New alerts, even if they are caused dueto events that triggered earlier alerts, get displayed as new rows in the table. You may still click on the greyedrows to view their details.

The maximum number of rows in this and other tables in GFMon can be configured from the Preferences Panel.

• System Memory Usage. This section displays the aggregate memory used across all active servers. Thehistogram on the right renders the memory used as a percentage of the total available memory across the serversover time. The vertical bar on the left shows a snapshot of the current memory usage. If the System MemoryUsage data is not available, then the X-axis is labeled Heap Memory Data is not Available.

• Resources Utilization Summary. This section provides an animated bar chart of individual memory and CPUusage on each member in the distributed system. The CPU usage bar and memory bar for each node are groupedtogether.

• Members Summary. Displays a tabular view of vital member statistics like:

• ID. The Member ID is a unique auto-generated value that identifies the member in the distributed system.• Name. The Name of the member. You can provide this name while starting GemFire through thegemfire.properties file or the name is inferred from the member ID.

• Host. The host on which the member is running.• Heap Usage. Displays the used heap memory of the member VM as a percentage of the maximum heap

memory.


• CPU Usage. Displays the percentage of the process CPU utilization.• Clients. Number of clients in the cache server, if applicable.• Uptime. Total time the node has been up and running.

Note: The Members Summary section displays the member ID for each member. Other informationpanels display the member name. If you do not configure a member name, GFMon constructs the membername from the member ID.

Double-click on a row in the Members Summary section to open the Details for member screen. The Detailsfor member screen provides additional information about each member.

• Rate of Cache Operations. This graph plots the get and put operations occurring per second over the periodof time specified.

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GFMon

• Regions Configurations. This table lists the attributes of the regions in the distributed cache. The table includesregion attributes like name, data policy, disk attributes, and backup persistence. The table also shows entrycount and entry size.

• Gateway Hub. If the member that you have selected is a Gateway, the Gateway Hub section is displayed. Thissection displays the listening port and the Gateway ID. The Find Points table displays the following:

• ID. The ID of the Gateway end point• Host/Port. The host name and port ID of the Gateway end-point• Connected. Whether the gateway is connected

Data Panel

The Data panel provides a bird's eye view of the GemFire data regions using pie charts. The Data panel alsoprovides details like scope, and data policy of each region across the members.


Note: The All Regions table lists Total Memory and % Memory only for regions that have a cap set onmemory use. For partitioned regions, this is set using the local-max-memory partitioned attribute. Forother regions, this is set by specifying lru-memory-size eviction for the region. When memory use is notlimited, these memory statistics are not captured in GemFire and are not displayed in GFMon.

The Region Members Details Viewer provides a tabular view of the following region attributes:

• Scope. For any region that is not partitioned, the region scope determines whether and how, region data isdistributed between the local cache and the rest of the distributed system.

• Data Policy. The data-policy attribute for each member determines which data is stored in the local cache.• Interest Policy. For each member, the interest-policy defines the entry operations that are delivered to the local

cached region.• Disk Attributes. Disk attributes determine where, and how, region data is overflowed or persisted to a disk.

You can define attributes templates inside the <cache> and <region> elements and assign IDs for later retrieval.• Cache Loader. A cache loader automatically loads data from an outside source, such as a database. In a

distributed region that is not partitioned, one member may host the cache server for the entire distributed region.Loading into a partitioned region requires a cache loader in every partition.

Members Panel

The Members panel displays the characteristics of each member in the distributed system, alerts specific to theselected distributed system member.

21

GFMon

• The bar chart in the Members panel displays the number of clients, CPU usage percentage, and the Queues foreach member in the distributed system at current time.

• Member Summary Viewer. This table lists the member attributes like ID, Name, Total Regions, Root Regions,Clients, Queues, Total memory (in MB), Gets/sec, Puts/sec, Threads, and Network Usage (KB). The memberID is a unique auto-generated value that identifies the member.

• Member's Clients. This table lists the details of the clients connected to each member. Select a member in theMember Summary Viewer table to view the following attributes for each of the member’s clients:

• Client ID. A unique auto-generated ID that identifies the client• Client Name. A Client short name extracted from the client ID. Displays 'N/A' if the name can't be extracted

from the Client ID.• Host. The name of the host the client is running on• Queue Size. The queue size for this client on the server that this client is connected to• Gets. The number of gets/sec that the client is executing on the cache


• Puts. The number of puts/sec that the client is executing on the cache• Cache Misses. The number of times a get operation on the client cache resulted in the data being fetched from

a server because it was not already present in the client cache• CPU Usage. The CPU usage of the client• Threads. The total number of threads in the client application• Cache Listener Invocations. The number of times the cache listener has been invoked

Client statistics are displayed only if statistic sampling and time statistics are enabled in the GemFire distributedsystem. You can enable these by setting the following properties in the gemfire.properties file:

statistic-sampling-enabled=trueenable-time-statistics=true

• Member Alerts Viewer. This table displays the Definition ID and Time for the alerts for the member selectedin the Members Summary Viewer. You can configure alerts for a member in the Alerts panel. This sectiondisplays the alerts that originated on the member since the last reset. For details, double-click on an alert.

Alerts Panel

You can create custom alerts in the Alerts panel. Custom alerts in GFMon allow you to receive a notificationwhen a specified system statistic of an active member in a distributed system reaches a specified threshold.GemFire JMX admin agent alerts GFMon (and the RMI clients) when the customized alert reaches the threshold.For more information about receiving e-mail alerts, see the GemFire documentation.

For detailed description of system statistics, see the information on Statistics in the GemFire documentation.

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GFMon

Create Custom Alerts

To create custom alerts in GFMon, follow these steps:

1. In the Create Alert Definitions section, enter a name for the alert.2. In the Select Statistics section, click Add.... The Choose Stats window is displayed.3. From the drop-down menu, choose the statistic type. The available statistics for the type you have chosen

are displayed in the Statistic Name section.4. Select the Statistic Name(s) and click the right-arrow to move them to the Statistics Type (Statistic name)

section. If you want to deselect any values, select the values in the Statistics Type (Statistic name) sectionand click the left-arrow button.


5. Click Select. The statistics that you have selected are displayed in the Select Statistics table. You can addmore values to the table by repeating the above steps. To remove a value, select the check-box in the Removecolumn and click Remove.

6. If you have selected more than one statistic value, you must apply a function to the statistics to create alerts:

a. In the Trigger section, select the check-box beside Apply Function. The drop-down list is populated withthe available functions.

b. Select the function that you want to use and specify either the Number (for which the statistic value mustbe greater than or less than) or the Range (within which the statistic value must fall).

Note: You can only create a function when you have multiple statistics selected.

7. Click Save to save the alert definition. The alert name is now displayed in the Available Alert Definitionssection.

8. To modify an alert definition, select the alert from the Available Alert Definitions section and click Edit.You can change the alert definition by editing the desired parameter. To delete an alert definition, select thealert from the Available Alert Definitions section and click Delete.

All alerts are displayed in the Alerts! section of the Overview panel.

The GFMon Event Viewer table displays warnings that are logged in the GFMon’s log file. You can view theinternal warnings and node information in the GFMon Event Viewer and see the log file for details. Double-clickany item in the table to get more information about the event. The Info Type scroll-bar allows you to scrollthrough all the events in the table. Use the Message scroll-bar to scroll through the complete message.

By default the GFMon Event Viewer displays the last 100 events only. Go to the General tab in the Preferencespanel to configure preferences:

• To change the number of events viewable in the GFMon Event Viewer, change the Maximum number of rowsviewable in a table preference.

• To change the logging severity/detail level of the GFMon’s log file, change the Logging Level preference.

The following events are logged in the event viewer:

PurposeEvent Type

When member joins the system.Node Joined

When a member crashes.Node Crashed

When a member leaves the system.Node Left

When a system alert occurs.Alert!

When a GFMon error occurs.Internal Error

When a GFMon warning occurs.Internal Warning

When GFMon attempts to reconnect to the JMX agent. This happens when the JMX agent shuts down

unexpectedly.

Reconnecting to the Agent!

When an attempt to reconnect to the JMX agent fails.Shutdown of the Agent!

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GFMon

Use the Clear and Clear All buttons at the bottom-right corner of the GFMon Event Viewer panel to clear theselected event or to clear all events.

Preferences Panel

The Preferences panel allows you to set connection and general preferences and save them for future use. OnWindows platforms, these preferences are saved in the system registry in the logged in theHKEY_CURRENT_USER\Software\JavaSoft\Prefs\Gemstone\GemFireMonitor\2.5\<Logged-In-User-Name> node. On Linux platforms, these preferences are saved inthe /home/<Logged-In-User-Name>/.java/.userPrefs/GemStone/GemFireMonitor/<encoded_version_info>/<Logged-In-User-Name>/prefs.xml file. The formatof the name of the encoded_version_info directory will be similar to _!$)!.g!w.

You can use the Connections tab to create connection preferences and store them for future use.


Create Connection Preferences

To create and use connection preferences:

1. In the Specify your connection by host name or IP address field, enter system name, host name, and portnumber.

2. Click Save. The information that you entered is populated in the Connect to stored sessions section.

Note: If you connect to a new agent, it is automatically populated in the Connect to stored sessionssection. The un-saved connections are denoted by an appended * (asterisk) in the Status column.

3. Highlight the row of the system name and click Connect or Disconnect as required.

Note: You can connect to one distributed system at a time

You can use General tab to set various preferences of your GFMon tool.

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GFMon

You can configure the following preferences in the General tab:

• Log file Directory. The directory where you want the GFMon log files to be stored. You can browse for thedirectory you want. Make sure the GFMon application has read/write access to the log files.

The default log file directory is <parent-directory>/GemStone/GemFire/GFMon/logs. The<parent-directory> is either the user's home directory or current working directory depending on theaccess assessed in the same order.

The log file name format is yyyy-MM-dd-HH-mm-ss-sss_<random_number>_gfmon.log. Forexample, 2009-01-19-19-10-36-234_8632816_gfmon.log is located in the log file directory. Foreach instance of GFMon, a new log file is created with a different name that depends on the timestamp and therandom number.

• Logging Level. The logging level from the available options in the drop-down menu. The default value is info.The valid logging levels are all, finest, finer, fine, config, info, warning, error, severe, and none. The logging


level all provides information of all severity levels, while the logging level severe provides the informationthat is logged at severe level.

Setting log-level to one of the ordered levels causes all messages of that level and greater severity to be printed.Lowering the log-level reduces system resource consumption while still providing some logging informationfor failure analysis.

• Refresh Interval. The number of milliseconds between updates for the data displayed in GFMon views. IfGFMon connects to an admin agent running GemFire version 6.0 or later, set the GFMon refresh interval tothe same value as the agent’s refresh-interval property. In systems running GemFire 6.6.2 or earlier, the agent'sdefault refresh interval is 5 seconds. In systems running GemFire 6.6.3, the agent's default refresh interval is15 seconds. For more information about configuring the refresh-interval property in the JMX adminagent, see the topic Starting an Admin Agent with a Non-Default Statistics Refresh Interval on page 16.

Note: The GFMon refresh interval is specified in milliseconds and the JMX Agent refresh interval isspecified in seconds.

Note: The refresh interval configured in the Preferences panel does not affect the refresh interval of theGemFire JMX admin agent. GemFire versions prior to GemFire 6.0 do not support the refresh-intervalproperty for the admin agent.

• Number of quick connect (host/port) entries to keep in history. The number of entries the Agent host andAgent port fields must retain in the Quick Connect section.

• X scale time range for Time Charts (in minutes). Define the time range that you want to plot the charts.• Reconnect. The number of times and time interval GFMon must attempt to reconnect (in the Number of retries

and Reconnect Interval in milliseconds fields) if the connection is lost.• Maximum number of rows in a table. The maximum number of rows that are kept in a table. For example,

you can configure the number of entries in the Alerts! table in the Overview panel and the GFMon EventViewer table in the Alerts panel.

After selecting the option or changing the value that you require, click Reset or Apply as applicable. Except forchanges to Log File Directory and Refresh Interval, the changes you make reflect immediately. The changes toRefresh Interval reflect when you connect to the agent subsequently. The changes Log File Directory reflectonly when you launch GFMon for the next time.

Status Bar

The status bar at the bottom of your GFMon window provides information and alerts about the session.

These are the alert icons and their meanings:

•This icon indicates a JMX connection

•

These icons indicate an alert•

This icon indicates a background job•

This icon is displayed after you connect to the distributed system. Click on it to see the Progress viewpanel, with information about agent connections and the alerts that you save.

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GFMon

Error Notifications Displayed by GFMon

During the following failure situations, GFMon displays a pop-up window reporting a fatal error:

• The JMX agent that GFMon is connected to shuts down. A pop-up window titled Fatal Error is displayed withthe message "JMX Agent has shut down"

• GFMon is started and running with a gemfire.jar file which is incompatible with the version of the gemfire.jarfile of the running JMX Agent. In this condition, a pop-up window titled Fatal Error is displayed. For example,if you run GFMon with the gemfire.jar file of GemFire version 5.7 to monitor a GemFire version 5.7.1 orGemFire version 5.8 distributed system, the message is:

GFMon could not connect to the GemFire Distributed System. This version of GFMon is compatible with GemFire Enterprise 5.7. GFmon encountered a Class Mismatch. Please shutdown GFMon and restart with a compatible GemFire version

• GFMon encounters an error during run-time while retrieving data from the JMX admin agent. A pop-up windowtitled Fatal Error is displayed with a message depending on the error that has occurred.

To fix the issue, close the pop-up window and perform the following procedure:

1. Turn off GFMon.2. Reset the environment variable GEMFIRE to point to the GemFire product location from which the admin

agent is running.3. Restart GFMon.


Chapter 2DataBrowser

The vFabric GemFire DataBrowser utility allows users to connect to a vFabric GemFire distributed system and querythe data interactively using OQL.

DataBrowser OverviewThe DataBrowser allows you to connect to a vFabric GemFire distributed system to browse data using ad-hocOQL queries.

DataBrowser is designed to work with GemFire versions 6.0 or higher.

Use DataBrowser to perform the following tasks:

• Execute ad-hoc queries on any data region on any cache node in the distributed system. The DataBrowserdisplays the results in a tabular format that allows you to drill to down into complex nested objects.

• Configure the maximum number of rows returned by any query to avoid excessive resource use on the server.• Simultaneously execute multiple continuous queries on one or more cache servers in the distributed system.

The DataBrowser continuously updates the results in a tabular window.• Provide security credentials when connecting to a distributed system through a plug-in mechanism.

DataBrowser System RequirementsVerify that your system meets the installation and runtime requirements for DataBrowser.

The DataBrowser is designed to run on Microsoft Windows and Red Hat Linux. DataBrowser requires the JavaRuntime Environment (JRE), 1.5 or higher to run.

DataBrowser requires vFabric GemFire 6.0 or higher (at runtime).

The minimum recommended hardware is a machine with Intel® 2 GHz Pentium® 4 (or equivalent) and 2 GBRAM.

You may want to explicitly set the JVM heap size in the DataBrowser startup scripts to a value suitable for thetypical result sizes returned by the queries that you run in your distributed system.

Installation and LicensingVerify the system and licensing requirements for DataBrowser and install the utility.

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Installing DataBrowser

To obtain DataBrowser, go to the VMware download center at http://downloads.vmware.com/d/. Navigate tothe vFabric GemFirfe download page, under the Drivers & Tools tab.

DataBrowser is distributed as a JAR archive. Execute the jar to file install the product. You will be promptedthrough a sequence of steps, including selection of the file system location in which the software is installed.

The DataBrowser tool installation has these directories:

• bin. The DataBrowser launch scripts, databrowser.bat and databrowser• docs. Contains an index.html page that links to the latest GemFire documentation (requires an Internet

connection) and an INSTALL.txt file.• lib. The jars and binary libraries needed to run DataBrowser

Uninstalling DataBrowser

To uninstall DataBrowser, delete the file system tree where you extracted the ZIP archive.

Licensing

DataBrowser uses GemFire licensing. The AdminAgent used by the DataBrowser to connect to the distributedsystem uses a GemFire license.

Using DataBrowser with GemFire Versions Earlier than 6.6

To use DataBrowser with GemFire versions earlier than 6.6, you may be required to provide a license on themachine where you are running DataBrowser. For example, you may require a license if your installation is notusing an evaluation or an unlimited client license. If necessary, specify license properties similar to the licenseproperties that you specify for GemFire clients. On the machine that you are running DataBrowser, set theJAVA_ARGS environment variable as follows.

On Windows:

set JAVA_ARGS="-Dgemfire.license-type=development -Dgemfire.license-file=C:\GemFireLicenses\development\gemfireLicense.zip"

On Linux:

export JAVA_ARGS="-Dgemfire.license-type=development -Dgemfire.license-file=/home/user1/GemFireLicenses/development/gemfireLicense.zip"

Ask your VMware account manager if you need additional licensing.

Running DataBrowserRun the installed DataBrowser with a running vFabric GemFire system.

DataBrowser connects to a running GemFire JMX admin agent to run its queries.

Note: DataBrowser creates a temporary directory on startup. Hence, the user should have write permissionsto the DataBrowser directory.

• In the GemFire product bin directory, execute agent start to start the AdminAgent in the GemFiredistributed system. Refer to Starting the vFabric GemFire JMX Agent in the GemFire User's Guide forinformation on starting the AdminAgent with non-default options. By default, the AdminAgent listens on port1099 for RMI clients.


http://downloads.vmware.com/d/

• Set the GEMFIRE environment variable to point to the product directory containing the same gemfire.jar usedby the AdminAgent.

• Add any application classes in the classpath. These can also be set in the DataBrowser's preferences.• To start the DataBrowser, execute databrowser.bat (Microsoft Windows) or the databrowser shell script (Linux).

Note: You may want to explicitly set the JVM heap size in these start scripts to a value suitable for theresult sizes that you expect for your queries.

• To specify SSL configuration for Data Browser when JMX Agent has SSL enabled, use the environmentvariable JAVA_ARGS. Windows example:

set JAVA_ARGS="-Djavax.net.ssl.keyStoreType=jks -Djavax.net.ssl.keyStore=/path/to/trusted.keystore-Djavax.net.ssl.keyStorePassword=password-Djavax.net.ssl.trustStore=/path/to/trusted.keystore-Djavax.net.ssl.trustStorePassword=password"

Linux example:

export JAVA_ARGS="-Djavax.net.ssl.keyStoreType=jks -Djavax.net.ssl.keyStore=/path/to/trusted.keystore-Djavax.net.ssl.keyStorePassword=password-Djavax.net.ssl.trustStore=/path/to/trusted.keystore-Djavax.net.ssl.trustStorePassword=password"

• Data Browser also connects as a cache client to GemFire Distributed System members that are running cacheservers . If the servers have SSL enabled, in addition to the above properties, you may need to specify additionalproperties such as the following when starting Data Browser:

• ssl-enabled• ssl-protocols• ssl-require-authentication• ssl-ciphers

For information on these properties, see SSL in the "Managing GemFire" section of the GemFire User's Guide.To specify these properties, use the environment variable JAVA_ARGS after adding a prefix "-Dgemfire"when starting up the DataBrowser. For example:

-Dgemfire.ssl-enabled=true-Dgemfire.ssl-protocols=any-Dgemfire.ssl-require-authentication=true-Dgemfire.ssl-ciphers=SSL_RSA_WITH_NULL_SHA"

The DataBrowser connects to a running AdminAgent to discover the data regions and cache servers in a GemFiredistributed system and display them in the user interface. Queries must be executed by selecting data region,and optionally, a member that is hosting the region. If no member is indicated, the DataBrowser automaticallyselects the first region host that it finds.

Note: The DataBrowser does not guard against executing complex queries such as those that do a joinacross regions on a cache server that does not have all the regions required by the query.

Connecting DataBrowser to a vFabric GemFire SystemIn the DataBrowser, connect to a running JMX admin agent in a vFabric GemFire distributed system.

33

DataBrowser

Once the DataBrowser is running, you can connect to a GemFire distributed system by clicking on the toolbaritem labeled 'Connect to GemFire...' or by selecting the File menu item of the same name. This displays the'Connect to GemFire distributed system' popup dialog.

The host and port fields refer to that of the RMI enabled AdminAgent in the GemFire distributed system towhich you want to connect.

These host port combinations are saved by the DataBrowser to allow you to easily select a previous AdminAgentfrom the drop down lists in this dialog. You can set the number of entries in this list in the Connection Preferencesdialog.

Once connected to the distributed system, the DataBrowser fetches the GemFire regions present in the distributedsystem, as well as the members on which they are located.

Note: RMI does not allow reserved characters in the host name, including '%', '$', and '-'. For a completelist of reserved characters consult RFC 952. If your host names contain non-compliant characters, werecommend using the IP address instead.

Tour of DataBrowserTo work in DataBrowser, you need to understand the screen layout and the options the browser provides.

Main Window

DataBrowser displays the Main Window at startup. All of DataBrowser's functionality is available through thiswindow.


Toolbar

Use the toolbar to access most of the functionality offered by the DataBrowser, including the ability to connectto and disconnect from a distributed system, specify security properties, execute queries, and export results toan XML file.

Menu

Use the menu Options item to set your preferences for the application. This displays the Preferences dialog thatallows you to set your preferences for connections made to distributed systems, query execution, securitypreferences, and other miscellaneous options such as additional classpath components for the application, locationof the log file, logging level among others.

35

DataBrowser

Region List

The region list shows the regions that are present in the distributed system. This information is refreshed accordingto the interval specified in the application preferences. The list is displayed as a tree where the child nodesrepresent child regions of a GemFire regions.

Member List

When a region is selected the GemFire members that have the region defined are displayed in the member list.Right-clicking on a member displays a context menu where you can execute a Continuous Query (CQ) on themember for the selected region.

Query Pane

The query pane is a multi-line editor where you can enter OQL queries for execution. If a line is selected, thetext on that line is the query string used for execution. If no line is selected, the text of the last line is automaticallyused as the query string for execution.

Results Pane

The results pane displays each results item in the table in the pane. Multiple tabs may be displayed under theresults pane, each tab representing a specific Java type returned in the results.

Continuous Query (CQ)

A Continuous Query is syntactically identical to a regular GemFire OQL query, except that once its is registeredon the member, the member continues sending result items that match the query specifications as changes happenin the region on the member.

The Continuous Query window has a single item in its toolbar that allows you to stop the execution of the CQ.It also shows some additional information about the query as it is being executed on the member. This includesthe total number of events that have occurred on the member since the CQ was registered, including inserts,updates and deleted.

Each Results tab in a ContinuousQuery window has a drop down list that contains the field (columns in the table)names of the items in the results. This is useful in filtering the results. Selecting a field in this list allows you tofilter the results displayed in the table by having it display only unique values for that field. For example, if oneof the fields in the query results is a zip code, applying a filter on that field will result in the table displayingonly a single row for each unique zip code returned by the query.

There is also an embedded pane that shows any messages or exceptions returned by the member.


Exporting Results to XML

You can export the contents of the Results pane in the Main Window to an XML file. The export also createsan associated XSD. This allows you to capture the results and manipulate it and examine it further using othertools at a later point in time.

Explore Functionality

The Results Pane in both the Main window and the CQ window has a context menu applicable to a single tablerow that allows you to drill down into the record in the result set. This is particularly useful to examine a recordthat contains fields that are collections or composite types.

To view custom application types, you must include the jars in the CLASSPATH or specify their location in theDataBrowser preferences.

DataBrowser PreferencesCustomize how DataBrowser works for you through the Preferences dialog.

User specified preferences can be set in the Preferences dialog, accessible through 'Options->Preferences...'.

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DataBrowser

Connection

These are the Connection options:

• Number of entries to keep in history list of AdminAgents to which you connected.• The timeout, in milliseconds, to be used on connection attempts to the AdminAgent.• The server response timeout, which is the amount of time, in milliseconds, for DataBrowser to wait for a

response from a server. This property is the same as the client pool attribute read-timeout

Query

Use this option to automatically append a specified LIMIT clause to each query, if one is not already present.This can help avoid out of memory situations in cases where the heap size of the VM used by the DataBrowseris not sufficient when the query results in extremely large data volumes being returned. This preference settingdoes not apply to CQs.

Security

Use the Security preferences to provide a jar that implements the GemFire security plug-in interface, and todefine properties to the interface for executing queries on a cache server.

The 'hidden' checkbox toggles the masked state of the values provided. Optionally, you can import propertiesfrom a property file by clicking on the 'Import' button.

The 'Security' group box, with security-specific UI controls, is also available in a pop-up when you click on the'Specify Security..' button on the Main Window toolbar.


Miscellaneous

With the Miscellaneous settings you can specify the following:

• Logging options. These are applied when you restart DataBrowser. These are the logging options:

• Location of the log files.• The maximum size of a log file. When a log file reaches this threshold, the log file is rolled over to a new log

file.• Number of rolled-over log files to store. When rolling over to a new log takes the total number of log files

over this limit, the oldest log file is deleted.

• The rate at which the DataBrowser updates its view of regions and members in the distributed system.• Custom application jars to add to the DataBrowser's classpath.

How DataBrowser WorksDataBrowser interacts with vFabric GemFire both as a GemFire client and as an RMI client of the AdminAgent.

39

DataBrowser

Discovery

As an RMI client, DataBrowser uses JMX to get information about the data regions in the distributed systemand the servers on which they are located. This information is displayed on the left side of the Main Window,where the data regions are displayed in a hierarchical tree, with child data regions displayed as sub-nodes oftheir parent data region. The lower pane on the left shows the list of cache servers on which the region selectedin the upper list is located.

Query Execution

A region must be selected to execute a query specified in the Query Pane. You may also select a cache serveron which the query will be executed. If no cache server is selected, then the first one listed in the Member Paneis chosen for the execution of the query. DataBrowser does not prevent execution of complex queries, such asthose creating a join across regions, on a cache server that does not contain the regions. In this case an errormessage, sent by query engine on the server is displayed.

DataBrowser creates a connection pool to a cache server the first time a query is executed on it. This pool usesthe default settings specified by GemFire. This connection pool is maintained until the DataBrowser applicationis shut down, or the DataBrowser received a notification that the member is no longer present in the distributedsystem either because it has left or crashed. Though only a single ad-hoc query can be executed at a time, multipleCQs may be executed simultaneously. If these queries are being executed on the same cache server, then multipleconnections to the cache server are automatically created.

DataBrowser uses the default settings of connection pools. These settings allow it to start with a single connectionand allow for unbounded number of connections in pool. The DataBrowser maintains a connection pool percache server, with a single connection in the pool. There is no fail-over to another cache server in case a connectionis lost. If a query is being currently executed on a cache server that leaves, an error is returned in the UI.

Security

DataBrowser supports the GemFire security mechanism. It attempts to execute a query without presenting anysecurity credentials to the cache server. If the distributed system is security enabled, then the DataBrowserreceived a security exception. It handles this by presenting a popup dialog populated with the name of the securityplugin jar and properties specified in the Preferences dialog. The user may modify these if needed, or simplyclick the OK button to have the DataBrowser use the default jar and the properties. Currently DataBrowser doesnot provide mechanism that filters the list of regions and cache servers displayed based on the security credentials.

Note: For details on GemFire security, see the vFabric GemFire User's Guide.


Connection by DataBrowser to GemFire Distributed System

For details on client connection pools, see the client/server topology information in the vFabric GemFire User’sGuide.

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DataBrowser

Chapter 3Visual Statistics Display

The Visual Statistics Display (VSD) utility reads GemFire statistics and produces graphical displays for analysis. VSDis an optional utility distributed separately from GemFire.

VSD OverviewVSD helps you monitor the performance of vFabric GemFire and diagnose performance problems.

For specific information on the statistics produced by vFabric GemFire, see the product documentation.

Your GemFire product creates a statistical archive file named filename.gfs. The file logs useful statistics— counters and gauges that describe the state of the system at a particular moment in time. The file collectsstatistics at specific sampling intervals, which you can set at various levels to monitor different types of behavior.

The VSD tool reads the sampled statistics and produces graphical displays for analysis. Typically, the points ona line of a VSD graph represent the values for a particular statistic over time. VSD’s extensive online help offersmore complete reference information about the tool.

The following screenshots of the VSD tool display statistics and a graph analysis of selected statistics.

43

:


VSD System RequirementsView a list of platforms that are known to work with VSD.

The following platforms are known to work with the current VSD release:

• Solaris 2.8• HP-UX 11.0• AIX 4.3• RedHat 3• RedHat 4• RedHat 5• RedHat 6• SLES 8• SLES 9• SLES 10• Windows NT 4.0• Windows 98/ME/2K• Windows XP SP3• Windows Server 2003• Windows Server 2008

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Visual Statistics Display

• Windows 7 (Note: Requires slight modification; see below.)

Windows 7 Support

To use VSD on Windows 7, perform the following steps:

1. Start Windows Explorer and navigate to the GemFireProductDir\vsd\bin\ directory (whereGemFireProductDir corresponds to the location where you unzipped the VSD distribution.)

2. Right click and select properties for vsd.bat.3. Select the Compatibility tab.4. Click "Run this program in compatibility mode for" and then select Windows XP SP3.5. Repeat steps 2 and 3 for all the other executables in the bin directory.

Mac OSX Support

In addition, VSD can be run on Mac OSX but requires the Mac OSX distribution, which is not part of the regularvFabric GemFire product download. Contact your VMware support representative to obtain the distribution.

Installing and Running VSDStart the VSD tool, load statistics files, and maintain the view you want on your statistics.

Install and Start VSD

VSD is a free analysis tool and is provided as-is.

To obtain and install VSD, perform the following steps:

1. Visit to the vFabric GemFire product download page athttp://downloads.vmware.com/d/info/application_platform/vmware_vfabric_gemfire/6_6.

2. On the vFabric GemFire product download page, click on the Drivers & Tools tab.3. Select VMware vFabric GemFire Visual Statistics Display and click View Download.4. Download the appropriate .zip file for your platform.5. To install the tool, unzip the files to the desired location on your machine.

To start VSD, enter this command:

gemFireProductDir/vsd/bin/vsd

where gemFireProductDir corresponds to the location where you unzipped the VSD distribution.

Load a Statistics File into VSD

You have several options for loading a statistics file into VSD:

• Include the name of one or more statistics files on the VSD command line. Example:

vsd <filename.gfs> ...

• Browse for an existing statistics file through Main > Load Data File.• Type the full path in the File entry box, then press Enter.• Switch to a statistics file that you’ve already loaded by clicking the down-arrow next to the File entry.

After you load the data file, the VSD main window displays a list of entities for which statistics are available.VSD uses color to distinguish between entities that are still running (shown in green) and those that have stopped(shown in black).


http://downloads.vmware.com/d/info/application_platform/vmware_vfabric_gemfire/6_6

Maintain a Current View of the Data File

If you select the menu item File > Auto Update, VSD automatically updates your display, and any associatedcharts, whenever the data file changes. Alternatively, you can choose File > Update periodically to update thedisplay manually.

About Statistics

Some statistics are cumulative from when the GemFire system was started. Other statistics are instantaneousvalues that may change in any way between sample collection.

Cumulative statistics are best charted per second or per sample, so that the VSD chart is readable. Absolutevalues are best charted as No Filter.

Viewing Statistics in VSDSelect statistics and view them using chart templates and customized charts.

Statistic Levels

Each statistic has a characteristic called a level that reflects the amount of background knowledge that you wouldneed to use the statistic with understanding. You can set up VSD to list (in its main window and in associatedcharts) only those statistics that are at, or below, a certain level of complexity — common, advanced, or wizard.

To establish the levels of statistics that you want to display in VSD, choose the menu item Main > Statistic Levelin the main VSD window.

Select Statistics for Viewing

1. In the VSD list, click the left mouse button to select the entity or entities you want to view.

• Search for a specific session name or process ID. To find a specific entity, click the mouse in the processlist, then press Ctrl-S. When the dialog box appears, enter the PID or name of the entity that you’re lookingfor. VSD highlights the first entity with that PID or name. To find the next match, press Ctrl-S again. Toselect the highlighted item, click on it. When you’re done, press Return.

• Select all entities or by statistic or by type. Statistics are available for various entities, which are listed underthe heading Type in the process list.

Note: You can use the right mouse button to perform these functions:

• Combine multiple entities into a single line. This can be quite helpful. For example, if you want tomeasure page reads per second for several hundred entities, you could select all the entities, thencombine them into a single line in the chart, thus rendering the data much more readable.

• Combine multiple entities from different files into a single line.• Eliminate flatlines — entities whose values are always zero.• Select Single File mode so only one loaded file can be enabled at a time.• Select for created lines to have absolute timestamps, which is useful when merging files.

2. Select a statistic for viewing from the statistics list just below the process list.3. With the selecting statistic, do one of the following:

• To display the statistic in a new chart, type the name of the chart in the Chart entry box, then click NewChart. (Note: If you don’t explicitly specify a chart name, VSD will assign one for you.)

47


• To display the statistic in an existing chart, select the chart name in the Chart entry box. Then click on AddLine.

4. To add another statistic to the chart, repeat steps 1 through 3.

Using VSD Chart Templates

VSD templates let you quickly add a set of lines to a chart. Templates are helpful if you find yourself performingthe same task frequently in VSD — for example, monitoring the same five or six statistics. By creating a templatefor the statistics that you want to monitor most frequently, you can automate the task of building charts.

In your template, you can assign a filter for each statistic, to determine how much information is displayed forthat statistic. You can also restrict the template to look for extreme conditions (for example, processes that areconsuming 90% or more of the CPU).

VSD is shipped with a set of predefined templates, which are maintained in the .vsdtemplates file in your homedirectory.

ProcedureTask

In the VSD main window, choose the menu item Template > New Template Chart. This is a good way

to display some of the more useful system statistics.

Create a new chart from a

template

In the Chart window, choose the menu item Chart > Add From Template. (Note: If you have zoomed in

on a chart, the template filter is only applied to values within the zoomed range.)

Apply a template to the chart

you are viewing

In the VSD main window, choose the menu item Template > Reload Template File.Reread the

.vsdtemplatestemplate file into VSD after

you’ve edited it

In the Chart window, configure the chart as you desire, then choose the menu item Chart > Save Template.

The template is saved to the .vsdtemplates file. If you save the current chart as a template, you

Save the current chart as a

template

may still need to edit the .vsdtemplates file so that you can give it a more useful name and

make the information and patterns it captures more general.

Chart Menu (Chart Window)

To customize the way VSD displays statistics in your chart, you can choose items from the Chart window’sChart menu.

EffectChart Menu Item

Expand template and add resulting lines to chart.Add from Template

Save all lines on chart as a template.Save Template

Paste last item on clipboard.Paste

Print chart.Print

Write this chart as a graphic to snapshot.gif.Snapshot

Open Help window.Help . . .

Zoom in to improve your view of the chart. After you choose this menu item, click to select one corner

of the area that you want to zoom. Move the mouse pointer to the opposite corner of the zoom area, then

Zoom In

click again. If you have a middle mouse button, you can quickly zoom in on an area by clicking the

middle mouse button over it.


EffectChart Menu Item

Zoom out by clicking the right mouse buttonZoom Out

Log information by comparing two points.Compare Two Points

Adjust the scale of the chart. This helps you view multiple statistics on the same axis.Compute Scale All, Unscale All

Display the legend for this chart.Show Legend

Change the format of the time displayed along the X axis.Time Format

Display the title alongside the respective axes.Show Time Axis Title, Show

Left Axis Title, Show Right

Axis Title

Display the current X and Y values for the selected line at the top of the chartShow Current Values

Display the minimum and maximum values for the selected line at the top of the chart.Show Min and Max

Display these statistics for the selected line: the number of data samples, the min, max, mean, and standard

deviation. The statistics are calculated from all of the data points on the selected line in the region defined

by the graph's current X axis. (To change the region, select Zoom In or Zoom Out from the Chart menu.)

Show Line Stats

Draw cross hairs on graph of item.Show CrossHairs

Draw grid line on graph of item.Show Grid Lines

Close chart window.Close

For additional information about the Chart window, choose Help from the Chart menu.

Line Menu (Chart Window)

Customize your VSD chart display using items from the Line menu (in the Chart window). Line menu commandsoperate on the currently selected line. To select a line, click on it or on its entry in the chart legend. VSD highlightsthe selected line.

EffectLine Menu Item

Display a log file showing the line statistics for all data samples in the region defined by the graph's

current X axis.

Log Info

Measure the difference between two values on the selected line. Select the line before choosing this menu

item then click on the two points whose difference you want to compute. VSD responds by displaying a

Log Delta

log file showing the difference in time and value between the two points; the number of data samples in

the selected line segment; and the min, max, mean, and standard deviation of those samples.

Compute a scale value for the selected line that will make it visible on the current chart. You can also

use the Scale entry box to manually change the scale. The default scale value is 1.

Compute Scale

Reverse the effect of Compute Scale.Unscale

Display the Y axis for the selected line to the left of the chart. Otherwise, the Y axis is displayed to the

right. You can use this to view multiple lines on the same chart, by graphing large values on one axis

and small values on the opposite axis.

Graph on Left Axis

Select a new symbol.Symbol

Select a line style for connecting points: linear (default), step, natural, quadratic.Style

Update files used by current line.Update

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EffectLine Menu Item

Add a line to the current line.Add Lines

Remove a line from the current line.Diff Lines

Divide current line by another line.Divide Lines

Normalize current line.Normalize

Trim line to left or right of a data point.Trim Left, Right

Undo any trim line operations.Untrim Left, Right

Copy current line to clipboard.Copy

Cut current line to clipboard.Cut

Remove the selected line from this chart.Delete

Customizing Your VSD Chart

You can customize and manipulate a VSD chart in many ways:

• To select a line in the chart, click on it or on its entry in the chart legend.• To delete a line from the chart, click the middle mouse button (if available) on its entry in the chart legend.

Alternatively, select the line’s entry in the chart legend and choose Line > Delete.• To find out about a specific point in a chart, hold the mouse pointer over it.

View Statistic Information

To view a description of the most recently selected statistic, along with information about its type, level, anddefault filter, go to the VSD main window, then choose the menu item Main > Show Statistic Info.

In the Statistic Information window, you can redefine the level and default filter for any VSD statistic.

• The statistic’s level — common, advanced, or wizard — allows you to determine whether the statistic isdisplayed in the VSD statistic list.

• Whenever you add a line to a chart, the filter determines how information is displayed for the selected statistic.

EffectDefault Filter

No Filter if the statistic represents a snapshot of a value. PerSecond if the statistic represents a value that

always increases.

Default

Display the raw values for the statistic with no filtering.No Filter

Display the difference between two consecutive samples of the statistic.PerSample

Display the difference between two consecutive samples of the statistic, divided by the number of elapsed

seconds between the two samples.

PerSecond

Display a running total of per-sample deltas for the statistic. Reset to zero when the delta is zero or

changes direction.

Aggregate

Once you have added the line to a chart, you can override its default filter by specifying a new filter from thedrop-down menu at the top of the Chart window.

If you leave the Statistic Information window up as you work, it changes to reflect the current statistic. In thisway, you can get a quick explanation of any statistic that you're currently examining.


GlossaryThis glossary defines terms used in vFabric GemFire documentation.

ACK wait threshold

A time-to-wait for message acknowledgment between system members.

administrative event

See event on page 55.

API

Application Programming Interface. GemFire provides APIs to cached data for Java applications.

Application Cache Node

One of two vFabric GemFire licenses you can obtain for custom evaluation or production. Application CacheNode is the vFabric Suite offering for vFabric GemFire. See Choosing a License Option Based on TopologyHowyou plan to use vFabric GemFire determines which GemFire license offerings are right for your system. Licensingrequirements for vFabric GemFire are based on your deployment topology. .

application program

A program designed to perform a specific function directly for the user or, in some cases, for another applicationprogram. GemFire applications use the GemFire application programming interfaces (APIs) to modify cacheddata.

attribute

Querying: A named member of a data object. The public fields and methods of an object may be accessed asattributes in the context of a query.

Region: See region attributes on page 61.

attribute path

A sequence of attributes separated by a dot (.), applied to objects where the value of each attribute is used toapply the next attribute.

blocking

A behavior associated with synchronization functions. Blocking behavior is exhibited as waiting for a signal toproceed, regardless of how long it takes. See also timeout on page 64.

cache

In-memory GemFire data storage created by an application or cache server for data storage, distribution, andmanagement. This is the point of access for Java applications for all caching features, and the only view of thecache that is available to the application. Cache creation creates a connection to the distributed system. See alsolocal on page 58 and remote on page 61.

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cache-local

Residing or occurring in the local cache.

cache.xml

Common name for the XML file that declares the initial configuration of a cache. This file is used to customizethe behavior of the GemFire cache server process and can be used by any Java application. Applications canalso configure the cache through the GemFire Java APIs. You can give this file any name.

cache event

See event on page 55.

cache listener

User-implemented plug-in for receiving and handling region entry events. A region’s cache listener is calledafter an entry in the local cache is modified. See also cache writer on page 52.

cache loader

User-implemented plug-in for loading data into a region. A region’s cache loader is used to load data that isrequested of the region but is not available in the distributed system. For a distributed region, the loader that isused can be in a different cache from the one where the data-request operation originated. See also netSearchon page 59 and netLoad on page 59.cache misses, where a requested key is not present or has a null value inthe local cache.

cache miss

The situation where an key’s value is requested from a cache and the requested key is not present or has a nullvalue. GemFire responds to cache misses in various ways, depending on the region and system configuration.For example, a client region goes to its servers to satisfy cache misses. A region with local scope uses its dataloader to load the value from an outside data source, if a loader is installed on the region.

cache server

A long-lived, configurable GemFire distributed system member process that can service client connections.

cache transaction

A native GemFire transaction, managed by GemFire and not by JTA. This type of transaction operates only ondata available from the GemFire cache in the local member. See also JTA on page 57 and global transaction onpage 56.

cache writer

User-implemented plug-in intended for synchronizing the cache with an outside data source. A region’s cachewriter is a synchronous listener to cache data events. The cache writer has the ability to abort a data modification.See also cache listener on page 52 and netWrite on page 59.

client

A GemFire application that is configured as a standalone distributed system member, with regions configuredas client regions. Client configuration uses the <client-cache> cache.xml element and the ClientCache API.


client region

A GemFire cache region that is configured to go to one or more GemFire servers, in a separate GemFire distributedsystem, for all data distribution activities. Among other things, client regions go to servers to satisfy cache misses,distribute data modifications, and to run single queries and continuous queries.

collection

Used in the context of a query for a group of distinct objects of homogeneous type, referred to as elements. Validcollections include the java.util.Collection as well as Set, Map, List, and arrays. The elements in a collectioncan be iterated over. Iteration over a Map traverses its entries as instances of Map.Entry. A region can also betreated as a collection of its values. See also QRegion on page 61.

commit

A transactional operation that merges a transaction’s result into the cache. Changes are made in an “all or none”fashion. Other changes from outside the current transaction are kept separate from those being committed.

concurrency-level

Region attribute that specifies an estimate of the number of threads ever expected to concurrently modify valuesin the region. The actual concurrency may vary; this value is used to optimize the allocation of system resources.

conflation

Combining entries in a message queue for better performance. When an event is added to queue, if a similarevent exists in the queue, there are two ways to conflate the events. One way is to remove the existing entryfrom wherever it resides in the queue, and add the new entry to the end of the queue. The other way is to replacethe existing entry with the new entry, where it resides in the queue, and add nothing to the end of the queue. InGemFire, region entry update events, server events going to clients, and gateway events going to remote distributedsystems can all be conflated.

connection

The connection used by an application to access a GemFire system. A Java application connects to its GemFiredistributed system when it creates its cache. The application must connect to a distributed system to gain accessto the GemFire functionalities. A client connects to a running GemFire server to distribute data and eventsbetween itself and the server tier. These client connections are managed by server connection pools within theclient applications. Gateways connect to remote site GemFire gateway hubs to distribute data events betweensites.

consumer

GemFire member process that receives data and/or events from other members. Peer consumers are oftenconfigured with replicated regions, so all changes in the distributed system arrive into the local cache. Clientconsumers can register subscriptions with their servers so that updates are automatically forwarded from theserver tier. See producer on page 60.

coordinator

The member of the distributed system that sends out membership views. This is typically the locator in GemFire.

data accessor

In the context of a region, a member configured to use a region, but not store any data for it in the member’slocal cache. Common use cases for data accessors are thin clients, and thin producer and consumer applications.

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Accessors can put data into the region and receive events for the region from remote members or servers, butthey store no data in the application. See also data store on page 54.

data entry

See entry on page 55.

data fabricAlso referred to as an in-memory data grid or an enterprise data fabric. vFabric GemFire is an implementationof a data fabric. A data fabric is a distributed, memory-based data management platform that uses cluster-wideresources -- memory, CPU, network bandwidth, and optionally local disk -- to manage application data andapplication logic (behavior). The data fabric uses dynamic replication and data partitioning techniques to offercontinuous availability, very high performance, and linear scalability for data intensive applications, all withoutcompromising on data consistency even when exposed to failure conditions.

Data Management Node

One of two vFabric GemFire licenses you can obtain for custom evaluation or production. For details onconfigurations that require a Data Management Node license and its associated upgrades, see Choosing a LicenseOption Based on TopologyHow you plan to use vFabric GemFire determines which GemFire license offeringsare right for your system. Licensing requirements for vFabric GemFire are based on your deployment topology..

data-policy

Region attribute used to determine what events the region receives from remote caches, whether data is storedin the local cache, and whether the data is persisted to disk. For disk persistence, writes are performed accordingto the cache disk-store configuration.

data region (region)

A logical grouping of data within a cache. Regions usually contain data entries (see entry). Each region has aset of region attributes governing activities such as expiration, distribution, data loading, events, and capacitycontrol. In addition, a region can have an application-defined user attribute.

data store

In the context of a region, a member configured to store data for the region. This is used mostly for partitionedregions, where data is spread across the distributed system among the data stores. See also data accessor on page53.

deadlock

A situation in which two or more processes are waiting indefinitely for events that will never occur.

destroy

Distributed: To remove a cached object across the distributed cache.

Local: To remove a cached object from the local cache only.

disk region

A persistent region.


disk-store

Cache element specifying location and write behavior for disk storage. Used for persistence and overflow ofdata. The cache can have multiple disk stores, which are specified by name for region attributes, client subscriptionqueues (for servers), and wan gateway queues.

distributed cache

A collection of caches spread across multiple machines and multiple locations that functions as a single cachefor the individual applications.

distributed system

One or more GemFire system members that have been configured to communicate cache events with each other,forming a single, logical system.

distributed-ack scope

Data distribution setting that causes synchronous distribution operations, which wait for acknowledgment fromother caches before continuing. Operations from multiple caches can arrive out of order. This scope is slowerbut more reliable than distributed-no-ack.

distributed-no-ack-scope

Data distribution setting that causes asynchronous distribution operations, which return without waiting for aresponse from other caches. This scope produces the best performance, but is prone to race conditions.

entry

A data object in a region consisting of a key and a value. The value is either null (invalid) or a Java object. Aregion entry knows what region it is in. An entry can have an application-defined user attribute. See also regiondata on page 61, entry key on page 55, and entry value on page 55.

entry key

The unique identifier for an entry in a region.

entry value

The data contained in an entry.

event

An action recognized by the GemFire system members, which can respond by executing callback methods. TheGemFire API produces two types of events: cache events for detail-level management of applications with datacaches and administrative events for higher-level management of the distributed system and its components. Anoperation can produce administrative events, cache events, or both.

eviction-attributes

Region attribute that causes the cache to limit the size of the region by removing old entries to make space fornew ones.

expiration

A cached object expires when its time-to-live or idle timeout counters are exhausted. A region has one set ofexpiration attributes for itself and one set for all of its entries.

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expiration action

The action to be taken when a cached object expires. The expiration action specifies whether the object is to beinvalidated or destroyed and whether the action is to be performed only in the local cache or throughout thedistributed system. A destroyed object is completely removed from the cache. A region is invalidated byinvalidating all entries contained in the region. An entry is invalidated by having its value marked as invalid.Region.getEntry.getValue returns null for an invalid entry.

In GemFire, expiration attributes are set at the region level for the region and at the entry level for entries. Seealso idle timeout and time-to-live.

factory method

An interface for creating an object which at creation time can let its subclasses decide which class to instantiate.The factory method helps instantiate the appropriate subclass by creating the correct object from a group ofrelated classes.

forced disconnect

Forcible removal of a member from membership without the member’s consent.

gateway

Configured inside a gateway-hub, a gateway defines a single remote distributed system site in a multi-siteinstallation and manages communication with the remote site. The gateway might have multiple endpointsassigned to a single remote site. The gateway also specifies queue management parameters for its endpoints.

gateway-hub

GemFire caching entity that represents its distributed system in a multi-site installation. The hub manages thegateways that send messages to other distributed system sites and listens on an incoming port for connectionsfrom remote gateways.

gemfire

Command-line utility that allows you to perform various GemFire management tasks from the command line,including locator start and stop, online disk store management, and logging management.

gemfire.properties

Common name for the file used for distributed system configuration, including system member connection andcommunication behavior, logging and statistics files and settings, and security settings. Applications can alsoconfigure the distributed system through the GemFire Java APIs. You can give this file any name.

global scope

Data distribution setting that provides locking across the distributed system for load, create, put, invalidate, anddestroy operations on the region and its entries. This scope is the slowest, but it guarantees consistency acrossthe distributed system.

global transaction

A JTA-controlled transaction in which multiple resources, such as the GemFire cache and a JDBC databaseconnection, participate. JTA coordinates the completion of the transaction with each of the transaction’s resources.See also JTA on page 57 and cache transaction on page 52.


HTTP

World Wide Web’s Hypertext Transfer Protocol. A standard protocol used to request and transmit informationover the Internet or other computer network.

idle timeout

The amount of time a region or region entry may remain in the cache without being accessed before beingexpired. Access to an entry includes any get operation and any operation that resets the entry’s time-to-livecounter. Region access includes any operation that resets an entry idle timeout and any operation that resets theregion’s time-to-live.

Idle timeout attributes are set at the region level for the region and at the entry level for entries. See alsotime-to-live on page 64 and expiration action on page 56.

initial capacity

Region attribute. The initial capacity of the map used for storing region entries.

invalid

The state of an object when the cache holding it does not have the current value of the object.

invalidate

Distributed: To mark an object as being invalid across the distributed cache.

Local: To mark an object as being invalid in the local cache only.

JDBC

Java DataBase Connectivity. A programming interface that lets Java applications access a database via the SQLlanguage.

JMX

Java Management eXtensions. A set of specifications for dynamic application and network management in theJ2EE development and application environment.

JNDI

Java Naming and Directory Interface. An interface to naming and directory services for Java applications.Applications can use JNDI to locate data sources, such as databases to use in global transactions. GemFire allowsits JNDI to be configured in a cache.xml configuration file.

JTA

Java Transaction API. The local Java interfaces between a transaction manager (JTS) and the parties involvedin a global transaction. GemFire can be a member of a JTA global transaction. See also global transaction onpage 56.

JVM

Java Virtual Machine. A virtual machine capable of handling Java bytecode.

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key constraint

Enforcing a specific entry key type. The key-constraint region attribute, when set, constrains the entries in theregion to keys of the specified object type.

listener

An event handler. The listener registers its interest in one or more events, such as region entry updates, and isnotified when the events occur.

load factor

Region attribute. The load factor of the map used for storing entries.

local

Local cache: The part of the distributed cache that is resident in the current member’s memory. This term is usedto differentiate the cache where a specific operation is being performed from other caches in the same distributedsystem or in another distributed system. See also remote on page 61.

Region with local scope: A region whose scope is set to local. This type of region does not distribute anythingwith other member’s in the distributed system.

Region shortcuts: In the RegionShortcut and settings, LOCAL means the scope is set to local. All client regionshave local scope. In the ClientRegionShortcut settings, LOCAL means the region does not connect to the client’sservers.

local scope

Data distribution setting that keeps data private and visible only to threads running within the local member. Aregion with local scope is completely contained in the local cache. Client regions are automatically given localscope.

locator

GemFire process that tracks system members and provides current membership information to joining membersso they can establish communication. For server systems, the locator also tracks servers and server load and,when a client requests a server connection, the locator sends the client to one of the least loaded servers. Seealso gemfire on page 56.

LRU

Least recently used. Used to refer to region entry or entries most eligible for eviction due to lack of interest byclient applications. GemFire offers eviction controllers that use the LRU status of a region’s entries to determinewhich to evict to free up space. Possible eviction actions are local destroy and overflow. See also resourcemanager on page 62.

machine

Any GemFire-supported physical machine or VMware Virtual Machine.

member

A process that has defined a connection to a GemFire distributed system and created a GemFire cache. This canbe a Java or Native Client application. This can also be a GemFire process such as a locator or cacheserver. Theminimal GemFire process configuration is a single member that is connected to a distributed system.


message queue

A first-in, first-out data structure in a GemFire system member that stores messages for distribution in the sameorder that the original operations happened in the local member. Each thread has its own queue. Depending onthe kind of queue, the messages could be going between two members of a distributed system, a client and server,or two members in different distributed systems. See also conflation on page 53.

mirroring

See replicate on page 62.

multicast

A form of UDP communications where a datagram is sent to multiple processes in one network operation.

named region attributes

Region attributes that are stored in the member memory and can be retrieved through their region attributes refidsetting. GemFire provides standard predefined named region attributes, that are stored using region shortcutrefids. You can use any stored attributes that you wish, setting an id when you create them and using the idsetting in the refid you want to use to retrieve them.

netLoad

The method used by GemFire to load an entry value into a distributed region. The netLoad operation invokesall remote cache loaders defined for the region until either the entry value is successfully loaded or all loadershave been tried.

netSearch

The method used by GemFire to search remote caches for a data entry that is not found in the member’s localcache region. This method operates only on distributed regions.

netWrite

The method used by GemFire to invoke a cache writer for region and region entry events. This method operatesonly on distributed regions. For each event, if any cache writer is defined for the region, the netWrite operationinvokes exactly one of them.

network partitioning

A situation that arises from a communications partition that causes processes to become unaware of one another.

OQL

Object Query Language, SQL-92 extended for querying object data. GemFire supports a subset of OQL.

overflow

Eviction option for eviction controllers. This causes the values of LRU entries to be moved to disk when theregion reaches capacity. Writes are performed according to the cache disk-store configuration.

oplog / operation log

The files in a disk-store used for the cache operations.

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partition

The memory in each member that is reserved for a specific partitioned region’s use.

partitioned region

A region that manages large volumes of data by partitioning it into manageable chunks and distributing it acrossmultiple machines. Defining partition attributes or setting the region attribute data-policy to partition makes theregion a partitioned region.

peer

A vFabric GemFire member application that is not configured as a client. Peer configuration uses the <cache>cache.xml element and the Cache API. Peers can also be configured as servers to client applications and asgateway-hubs to remote distributed systems.

persistent region

A region with the attribute data-policy set to persistent-replicate.

persistent-partition

A region attribute setting identifying a region as a partitioned region whose data is persisted to disk. Withpersistence, all region entry keys and values are stored in an operation log on disk as well as being stored inmemory. Also referred to as disk region. Writes are performed according to the cache disk-store configuration.

persistent-replicate

A region attribute setting identifying a region as a replicate whose data is persisted to disk. With persistence, allregion entry keys and values are stored in an operation log on disk as well as being stored in memory. Alsoreferred to as disk region. Writes are performed according to the cache disk-store configuration.

producer

A GemFire member process that puts data into the cache for consumption by other members. Producers may beconfigured with empty regions, where the data they put into the cache is not stored locally, but causes cacheupdate events to be sent to other members. This is a common configuration in peer members and for clientprocesses. See consumer on page 53.

pull model

Data distribution model where each process receives update only for the data in which the process has explicitlyexpressed interest. In a GemFire peer member, this is accomplished using a distributed, non-replicated regionand creating the data entries that are of interest in the local region. When updates happen for the region in remotecaches, the only updates that are forwarded to the local cache are those for entries that are already defined in thelocal cache. In a GemFire client, you get pull behavior by specifically subscribing to the entries of interest. Seepush model on page 61.

pure Java mode

Running GemFire without the use of the GemFire native library. GemFire can run in this mode with limitedcapabilities.


push model

Data distribution model where each process receives updates for everything in the data set. In a GemFire peermember, this is accomplished using a replicated region. All data modifications, creations, and deletes in remotecaches are pushed to the replicated region. In a GemFire client, you get push behavior by registering interest inall keys in the region. See pull model on page 60.

QRegion

The region object representation in a GemFire query. A QRegion extends com.gemstone.gemfire.cache.Regionand java.util.Collection so that the single region specification can provide access both to region attributes andto region data collections such as keys and entry values. See also collection on page 53.

query string

A fully-formed SQL statement that can be passed to a query engine and executed against a data set. A querystring may or may not contain a SELECT statement.

race condition

Anomalous behavior caused by the unexpected dependence on the relative timing of events. Race conditionsoften result from incorrect assumptions about possible ordering of events.

range-index

An XPath index optimized for range-queries with the added index maintenance expense of sorting the set ofvalues. A range index allows faster retrieval of the set of nodes with values in a certain range. See alsostructure-index on page 63 and value-index on page 65.

region

A logical grouping of data within a cache. Regions usually contain data entries (see entry on page 55). Eachregion has a set of region attributes governing activities such as expiration, distribution, data loading, events,and capacity control. In addition, a region can have an application-defined user attribute.

region attributes

The class of attributes governing the creation, distribution, and management of a region and its entries.

region data

All of the entries directly contained in the region.

region entry

See entry on page 55.

region shortcut

Enums RegionShortcut and ClientRegionShortcut defining the main region types in GemFire for peers/serversand clients, respectively. Region shortcuts are predefined named region attributes.

remote

Resident or running in a cache other than the current member’s cache, but connected to the current member’scache through GemFire. For example, if a member does not have a data entry in the region in its local cache, itcan do a netSearch in an attempt to retrieve the entry from the region in a remote cache within the same distributed

61

system. Or, if the member is a client, it can send a request to a server in an attempt to retrieve the entry from theregion in a remote server cache in the server’s distributed system. In multi-site installations, a gateway sendsevents from the local cache to remote caches in other distributed systems. See also local on page 58.

replicated region

A region with data-policy set to replicate or persistent-replicate.

replicate

Region data-policy specification indicating to copy all distributed region data into the local cache at regioncreation time and to keep the local cache consistent with the distributed region data.

resource manager

GemFire process that works with your JVM’s tenured garbage collection (GC) to control heap use and protectyour JVM from hangs and crashes due to memory overload. The manager prevents the cache from consumingtoo much memory by evicting old data and, if the collector is unable to keep up, by refusing additions to thecache until the collector has freed an adequate amount of memory. Eviction is done for regions configured forLRU eviction based on heap percentage. See also LRU on page 58 and eviction-attributes on page 55.

role

The purpose a member fills in a distributed system, or how a member relates to other members. These optionalmembership roles specify the circumstances under which a member continues operation after incidents such asnetwork failures. Members can fill one or more roles. Any number of members can be configured to satisfy thesame role, and a member can be configured to play any number of roles.

rollback

A transactional operation that excludes a transaction’s changes from the cache, leaving the cache undisturbed.

scope

Region attribute: In non-partitioned regions, a distribution property for data identifying whether it is distributedand, if so, whether distribution acknowledgements are required and whether distributed synchronization isrequired. A distributed region’s cache loader and cache writer (defined in the local cache) can be invoked foroperations originating in remote caches. A region that is not distributed has a local scope. See also replicate onpage 62 and Data Management Node on page 54.

Querying: The data context for the part of the query currently under evaluation. The expressions in a SELECTstatement’s FROM clause can add to the data that is in scope in the query.

SELECT statement

A statement of the form SELECT projection_list FROM expressions WHERE expressions that can be passedto the query engine, parsed, and executed against data in the local cache.

serialization

The process of converting an object or object graph to a stream of bytes.

server

A GemFire member application that is configured as a peer in its own system and as a server to connectingGemFire client applications.


server group

An optional logical grouping of servers in a server distributed system. There is always the default server groupmade up of all available server in the server distributed system. Clients can specify the server group in theirserver pool configuration. Then the pool only connects to those servers. If no group is specified, the default isused.

server connection pool

The cache entity that manages client connections to servers.

socket

The application interface for TCP/IP communications. UDP provides unicast and multicast datagram sockets,while TCP provides server and connection sockets. TCP server sockets are used by server processes to createconnection sockets between the server and a client.

SQL

Structured Query Language.

SSL

Secure Socket Layer. A protocol for secure communication between Java VMs.

standalone distributed system

A distributed system configured for no communication with peers. Client applications are generally defined withstandalone distributed systems, so there is no peer communication and all event and data communication is donebetween the client member and the server tier.

statistics enabled

Region attribute. Specifies whether to collect statistics for the region.

struct

A data type that has a fixed number of elements, each of which has a field name and can contain an object value.

structure-index

An XPath index that is basically a pre-computed query. Any legal XPath expression can be used. The indexmaintains lists of all nodes that match the expression used to create it. If a query is performed that has the sameexpression as the index then the result is available without XPath evaluation. See also range-index on page 61and value-index on page 65.

system member

See machine on page 58.

TCP

The Transmission Control Protocol is a part of the internet protocol (IP) suite that provides unicast communicationswith guaranteed delivery. The TCP protocol is connection-based, meaning that a TCP socket can only be usedto send messages between one pair of processes at a time. Compare to UDP on page 64.

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timeout

A behavior associated with synchronization functions. Timeout behavior is exhibited as refusal to wait longerthan a specified time for a signal to proceed. See also blocking on page 51.

time-to-live

The amount of time a region or region entry may remain in the cache without being modified before beingexpired. Entry modification includes creation, update, and removal. Region modification includes creation,update, or removal of the region or of any of its entries.

Time-to-live attributes are set at the region level for the region and at the entry level for entries. See also idletimeout on page 57 and expiration action on page 56.

transaction

See cache transaction on page 52 and global transaction on page 56.

transaction listener

User-implemented plug-in for receiving and handling transaction events. A transaction listener is called after atransaction commits. See also transaction writer on page 64.

transaction writer

User-implemented plug-in intended for synchronizing the cache with an outside data source. A transaction writeris a synchronous listener to cache transactions. The transaction writer has the ability to veto a transaction. Seealso transaction listener on page 64.

transactional view

The result of a history of transactional operations for a given open transaction.

transport layer

The network used to connect the GemFire system members in a GemFire system.

TTL

See time-to-live on page 64.

UDP

The User Datagram Protocol is a part of the internet protocol (IP) suite that provides simple, unreliable transmissionof datagram messages from one process to another. Reliability must be implemented by applications using UDP.The UDP protocol is connectionless, meaning that the same UDP socket can be used to send or receive messagesto or from more than one process. Compare to TCP on page 63.

unicast

A message sent from one process to another process (point-to-point communications). Both UDP and TCPprovide unicast messaging.

URI

Uniform Resource Identifier. A unique identifier for abstract or physical resources on the World Wide Web.


user attribute

An optional object associated with a region or a data entry where an application can store data about the regionor entry. The data is accessed by the application only. GemFire does not use these attributes. Compare to regionattributes, which are used by GemFire.

value constraint

Enforcing a specific entry value type. The value-constraint region attribute, when set, constrains the entries inthe region to values of the specified object type. Value constraints can be used to provide object typing for regionquerying and indexing. The value-constraint is only checked in the cache that does the entry put or createoperation. When the entry is distributed to other caches, the value constraint is not checked.

value-index

An XPath index that operates much as a structure-index does, but that separates the nodes that match the XPathexpression into sets mapped by each node’s value. This allows further filtering of the nodes to be evaluated ina query by going directly to those with a specific value. See also structure-index on page 63 and range-indexon page 61.

view

A collection of member identifiers that defines the membership group in JGroups.

Virtual Machine

A completely isolated operating system installation within your normal operating system. This is generallyimplemented by software emulation or hardware virtualization.

VMware virtual machine

Also referred to as a VMware VM. A VMware VM is a tightly isolated software container that can run its ownoperating systems and applications as if it were a physical computer. A VMware VM behaves exactly like aphysical computer and contains it own virtual (ie, software-based) CPU, RAM hard disk and network interfacecard (NIC). An operating system can't tell the difference between a VMware VM and a physical machine, norcan applications or other computers on a network. Even the VMware VM thinks it is a "real" computer.Nevertheless, a VMware VM is composed entirely of software and contains no hardware components whatsoever.

XML

EXtensible Markup Language. An open standard for describing data, XML is a markup language similar toHTML. Both are designed to describe and transform data, but where HTML uses predefined tags, XML allowstags to be defined inside the XML document itself. Thus, virtually any data item can be identified. The XMLprogrammer creates and implements data-appropriate tags whose syntax is defined in a DTD file or an XMLschema definition.

XML schema

The definition of the structure, content, and semantics used in an XML document. The XML schema is a supersetof DTD. Unlike DTD, XML schemas are written in XML syntax, which, although more verbose than DTD, aremore descriptive and can have stronger typing. Files containing XML schema definitions generally have the xsdextension.

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XPath

A language that describes a way to locate and process items in Extensible Markup Language (XML) documentsby using an addressing syntax based on a path through the document's logical structure or hierarchy.


Documents

vFabric GemFire Tools - VMware Documentationpubs.vmware.com/.../PDF/vfabric-gemfire-tools-ug-6.6.4.pdf2009/01/19 · vFabric GemFire Tools VMware vFabric GemFire GFMon 2.7 VMware vFabric