Sasken Confidential © 2009 Sasken Communication Technologies Future of TTCN-3 Power Management and Testing Infrastructure 3 May 2012

Sasken Confidential © 2009 Sasken Communication Technologies

Future of TTCN-3Power Management and

Testing Infrastructure

3 May 2012

2© 2009 Sasken Communication Technologies

• The paper is proposed as a value addition in the Future of TTCN-3, for support of the system power management testing aspects.

• The presentation describes new areas of challenges, issues, use cases and test solution of the power management in an embedded/mobile system.

• The power management testing aspects will provide better system evaluation and help in tuning the system for optimal power usage in various possible scenarios.

Paper proposition


• The objective of power management system is to turn off or switch the system to a low power state when inactive.

• The evolution of the embedded devices and cell phones is manifested both by growth in units shipped and a persistently snowballing feature set. Manufacturers add these features under the competitive pressures of curtailing cost and maximizing talk time and stand by power.

• TTCN-3 should support the power measurements and testing aspects and test automation at all levels of the system starting from the IC chip boards to the drivers, application framework and applications.

• The advantages of power management:1. Reduce overall power consumption2. Maximize battery life 3. Lower power consumption means lower heat

dissipation which increases system stability4. Less power consumption will save money and

reduce impact on the environment

Why Power Management?


What is Power Management?–(1/2)

• To save power, obvious choice is to power off the device when not in use. The problem is when user keeps using the device very frequently, switching off and switching on each time consumes more power than keeping it powered on.

Avoid polling: Applications have to avoid unnecessary polling. Though polling many times will be simple solution, every time application polls, CPU wakes up from idle state, thus consuming more power.

Group timers: Polling may not be completely avoidable. If polling is required, applications that use timers can be grouped such that all applications polls almost at the same time to avoid multiple wake ups of CPU.


What is Power Management?–(2/2)

• Unused devices: If a device is no longer used by application, it has to be closed. If it is kept open even though it is not required, kernel will assume that device is in use. As a result, device will not go to power saving state. Of course, there will be inactivity timer which will make sure device goes to power saving state.

• Sufficient buffers: Allocate enough buffers to avoid frequent access to external memory.


Gaps in the TTCN Test System

• References in power testing:

• Using TTCN-3 to Design Performance Tests, presented by George Din, Cosmin Rentea at TTCN-3 User Conference 2006, June 2nd 2006, Berlin. This system proposes the general performance testing and does not refer to power measurements in specific.

• Some papers are there in the distributed testing of the electric power measurements domain.

• None of the solutions searched on the internet showed up the power management and testing infrastructure on the TTCN-2 & 3 systems for the embedded handsets!!

• This is the gap the paper proposes to address, the value add of power management and testing infrastructure on the embedded handsets.

• Many proprietary power test systems exist. E.g. http://elinux.org/OMAP_Power_Management


Power Management Use Cases

• Linux system is managed by either Advanced Power Management (APM) or Advanced Configuration and Power Interface (ACPI).The core power driver was added to the Linux kernel in order to facilitate low level drivers to control the peripherals supported by the Power Manager.

• Multimedia : As codecs is CPU intensive it drains power. So a state machine to save & resume the decoding state in case of an interrupt/error is beneficial.

• Messaging and Browser: Applications should avoid parsing the data for XML, codecs etc. often as this is very CPU intensive and drains power.

• Device Management : The firmware/application updates are power intensive hence they should consider having the delta firmware memory updates and not complete firmware updates.

• Memory operations should be limited as they consume power. One possible way is to allocate a chunk of memory and then keep using and free the chunk at the application quit time only.


Future of TTCN-3TTCN-3 Test Infrastructure

3 May 2012


TTCN3 Architectural Blocks

• Support from the TTCN-3 is as elucidated below:

The Platform Adapter (PA) should offer operations for handling absolute time and real time platform integrations.

The Component Handler (CH) should support time synchronization or test system architecture should be extended by a time synchronization interface.

The PA and CH should support multiple cores Symmetric multi-processing also for multiple core platforms testing.

For high performance real-time distributed testing all operations of the TTCN-3 test system should have deterministic time behavior. This can be realized by using real-time operation system and real-time programming (e.g. JRTS) for developing TTCN-3 test system.


TTCN-3 Architecture

Note: Diagram from: http://www.ttcn-3.org/Testsystems.htm


TTCN-3 System Details – (1/2)

• TTCN-3 is used to specify tests, the order of execution and a test system to execute the TTCN-3 tests.

• TRI and TCI standards define test system architecture.

• TTCN-3 tools are required to support internal interfaces.

• Allows reuse of test platform components with different tools but also for different System Under Tests (SUTs).

• The construction of a TTCN-3 test system requires A TTCN-3 test suite.

• A TTCN-3 tool, i.e., a TTCN-3 compiler (or interpreter) plus execution environment .


TTCN-3 System Details – (2/2)

• Optionally implementations for test execution control, logging and codecs.(Most commercial tools offer default implementations for these entities).

• A SUT Adapter implementing the means of communication required by SUT platform interfaces.

• A Platform Adapter implementing a timing model, e.g., power timing clock, and external platform functions (if there are any defined in the test suite).


Future of TTCN-3Power Management TTCN-

3 Test Infrastructure

3 May 2012


Power Management Test Architecture in TTCN-3

System Under Test

SUT Adapters

(Platform Calls)

Platform

Adaptors(OS

call)

TTCN-3 Test System

TTCN-3 Executable

Test

ControlLogging Codecs

Test System Executor

GraphicsSession

Manager

User

Interface

Hardware & driversHardware & drivers

OS layerOS layer

Protocols &

Libraries

Protocols &

Libraries

Application

Framework

Application

Framework

ApplicationsApplications

Mobile Handset

Hardware, drivers,

battery, CPU tests

Hardware, drivers,

battery, CPU tests

OS calls testsOS calls tests

Protocols &

network tests

Protocols &

network tests

Monkey tests,

benchmark tests

Monkey tests,

benchmark tests

Multimedia,

Browser, DM

applications tests

Multimedia,

Browser, DM

applications tests

Pow

er

Managem

ent

Test

s


Power Management Tests Functionality – (1/2)

• The power management test automation suite helps run the power management functionality tests and report results for:

CPU frequency

CPU idle

CPU state

CPU Active durations

CPU Sleep

Peripheral power usage

• There could be graphs like:

Power versus time

CPU frequency versus time

CPU frequency versus power

Memory versus power etc.


Power Management Tests Functionality – (2/2)

• E.g. Power TOP could give the CPU states of the processes. That could further be analyzed and based on the results system CPU, drivers and software could be fine tuned for optimized power.

• CPU consolidation test cases should be executed for multiple numbers of CPUs. If system is hyper threaded but number of CPU is 1 then some of the test cases will be executed. For better coverage of test cases there should be support for selecting a system which is at least quad core and then hyper threaded so that multiple CPU's testing could be covered. This would require the Symmetric multi-processing techniques to be supported. And also real time support.

• Timer migration and Symmetric multi-processing functionality verification test cases should be executed only on suitable architecture like quad core or multiple CPUs.


Power Management Test System Flow

Test Control

Logging

Codecs

Test System

Executor

Graphics

Session

Manager

User

InterfacePlatform

Adaptors(OS )

Hardware,

drivers, battery,

CPU tests

Hardware,

drivers, battery,

CPU tests

OS calls testsOS calls tests

Protocols &

network tests

Protocols &

network tests

Monkey tests,

benchmark tests

Monkey tests,

benchmark tests

Multimedia,

Browser, DM

applications tests

Multimedia,

Browser, DM

applications tests

Pow

er

Managem

ent

Test

s

Battery Levels

CPU details

Memory details

Time measures

Solution to

measure

platform data

TRI

Interfaces

TCI Interfaces

SUT Adapters

(Platform

Calls)

Power vs. Time Graph


Support in TTCN-3 for Physical Layer of Testing

• The physical layer of the batteries, CPU, clock etc.: access, continuous signals and physical environment.

• Platform adapter and TRI interfaces will help to access the physical layer registers, events and triggers from hardware and set, monitor them in the test control and logging modules.

• The implementation would cover particular platform adaptors for various mobile platforms and mobile OSes.

• The implementation of PA/SA is specialized for each cellular devices for platform related and system related aspects like drivers, OS calls and peripherals.

• The PA and CH should support multiple cores Symmetric multi-processing also for multiple core platforms testing.

• The TTCN-3 executable will contain the power management tests module.


Support in TTCN-3 for the Testing of Power Management

• Test control & execution would allow tester to configure different parameters, timing related and iteration related parameters. The TCI interfaces will integrate this with the TTCN-3 executable.

• Logging would log all the power parameters tested for a session.

• Test system executor, will contain the session management. It would also manage multiple sessions during testing. This would help the tester to have multiple application sessions run and evaluate the power parameters across the system. The session manager will receive all the inputs from logging and test control during a session.

• Graphics support can be used to plot the power graphs. This can be incorporated in TTCN-3 executable.

• TTCN-3 test System executor would have a user interface to take in user inputs/display power test results as tables/graphs.


Benefits and Advantages

• The organizations benefits are as anticipated below:

Cellphones, smart phones and other embedded device manufacturers demand increasingly complex power management chipsets and software systems while driving lower cost. The TTCN-3 must enable manufacturers to satisfy these needs.

At system level a TTCN-3 software environment allows rapid debug and release to production.

An architecture that supports high parallel efficiency and power allows manufacturers to take advantage of multiple CPU systems.

TTCN-3 enables solid repeatability and reproducibility, supports fast threshold determination and be able to make accurate differential measurements.


Conclusion

• With TTCN-3 test tools, test engineering organizations are well-positioned to deliver on-time, cost effective solutions into production.

• The addition of the test infrastructure of the power management aspects in the TTCN-3 would empower the accomplishment of testing characteristics.

• The test outcomes would further aid to fine tune the system and hardware parameters and application parameters as essential.


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Sasken Confidential © 2009 Sasken Communication Technologies Future of TTCN-3 Power Management and Testing Infrastructure 3 May 2012