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COMPUTER
ORGANIZATION
COMPUTER
• COMPUTING MACHINE USER
HARDWARE SOFTWARE
SOFTWARE
APPLICATION SOFTWARE
SYSTEM SOFTWARE
OPERATING SYSTEM
OPERATING SYSTEM
• USER-HARDWARE INTERACTION
• NEEDED TO MAKE USE CONVENIENT AND EFFICIENT
• PREVENTS USER PROGRAMS FROM INTERFERING WITH THE PROPER OPERATION OF THE SYSTEM
WHAT IF NO
O/S ?
O/S IN SIMPLE WORDS
I/OOPERATIONS
FILESYSTEM
ERRORDETECTION
RESOURCEALLOCATION
PROGRAMEXECUTION
O/S
COMING TO TECHNICAL VIEW POINT
• Processor management.
• Memory management.
• Device management.
• Application Interface
• User Interface.
KERNEL
Layered structure of
an O/S
A SIMPLE DIAGRAM WILL MAKE IT MORE CLEAR
? What does it do?
OPERATING SYSTEMOPERATING SYSTEM
AA MMOOEEBBAA
SHORT INTRO.
• Amoeba is the fastest growing multi-kernel distributed operating system
• Developed by Andrew Tanenbaum
• First prototype was released in 1983
• The last official update by original developers was in 1996
• Others have developed their own versions
– Fireball Amoeba by Fireball Software Distribution
GOALS OF AMOEBA
DistributionConnecting together many machines.
ParallelismAllowing individual jobs to use multiple CPUs
easily.
TransparencyHaving the collection of computer act like a single system.
PerformanceAchieving all of the above in an efficient manner.
KEY CONCEPTSMicro-kernel
– A simple micro-kernel is the basis for Amoeba
– Each machine in AMOEBA system runs a small identical software programe called a micro-kernel
– Communication b/w client processes & server process
– It handles the memory management, I/O, communication, object primitive, and basic processes
KEY CONCEPTS
• Remote Procedure Calls (RPC)– Used for communication between client and server
• FLIP– Fast Local Internet Protocol
– Developed by Andrew Tanenbaum.
– Designed to optimize the speed of RPCs
KEY CONCEPTS
• Security– 128 bit value known as CAPABILITY.– Used to verify that the user has permission to access
the object.– Capabilities are encrypted
• Directory Server– Handles naming of files– Knows the physical location of each file– Most files can be sent in a single RPC
ARCHITECTURE
• 4 main partS to Amoeba’s Architecture
– Workstations– Processor Pool– Servers– WAN Gateway
BECOMING FAMILIAR WITH
AMOEBA
LOG IN WINDOW
DESKTOP
SOME OTHER APPS.
ADVANTAGES OF AMOEBA
• Can use older/slower CPUs to create powerful system, need not to be of the same architecture (can mix SPARC, Motorola PowerPC, Intel, Pentium, etc.) so your old systems won’t be useless now !
• Micro-Kernel allows for other file systems to be created
• Initially Unix emulation was added by developers to make it compatible with commonly used systems of that time so they have many common commands
ADVANTAGES OF AMOEBA
• Developed from scratch so has the potential to
add compatibility with devices.
• System can be modified easily by a programmer according to requirements.
• It efficiently makes the connected system work with maximum potential
• Process is never swapped out.
Disadvantages
• Can only hold programs as large as its physical memory
• It has not had an official update in over 10 years
• Designed to run on machines with large amounts of RAM and huge local disks
• Process occupies contiguous segments in memory which may give rise to fragmentation
THANKYO
U