03-09-2007
pthread performance question
Running dedicated on AIX with 4 processors, creating 4 threads, each with equal work to do, only runs about 20% faster than 1 thread with all of the work. Test case has no blocking but does share memory for read access only.
Any ideas why I'm only seeing 20% gain? Is this typical on AIX? Anything I can do to improve system?
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LEARN ABOUT MINIX
threads
Portable Threads Abstraction Classes(3) Coin Portable Threads Abstraction Classes(3)
NAME
Portable Threads Abstraction Classes -
Classes
class SbBarrier
The SbBarrier class implements the 'barrier' multi-thread synchronization technique.
A barrier is a synchronization mechanism that is used for blocking threads as they enter the barrier until a given number of threads are
blocked, at which point all the threads are released again. "
class SbCondVar
A class for synchronizing access to global variables.
Condition variables are used to protect global variables in an environment where multiple threads are running concurrently. "
class SbFifo
A class for managing a pointer first-in, first-out queue.
class SbMutex
A basic class for managing a mutex.
This class provides a portable framework around the mutex interface of the underlying native thread-handling toolkit. "
class SbThreadAutoLock
Simple convenience class for locking access to a function.
This class provides a simple convenience mechanism for automatically locking access to a function that is not re-entrant. "
class SbRWMutex
class SbStorage
The SbStorage class manages thread-local memory.
This class manages thread-local memory. When different threads access the memory an SbStorage object manages, they will receive different
memory blocks back. "
class SbTypedStorage< Type >
The SbTypedStorage class manages generic thread-local memory.
This class manages thread-local memory. When different threads access the memory an SbTypedStorage object manages, they will receive
different memory blocks back. "
class SbThread
A class for managing threads.
This class provides a portable framework around the tasks of instantiating, starting, stopping and joining threads. "
Detailed Description
Coin implements a set of abstractions over the native threads data types that can be portably used across all the platforms Coin has been
ported to.
Author
Generated automatically by Doxygen for Coin from the source code.
Version 3.1.3 Wed May 23 2012 Portable Threads Abstraction Classes(3)