12-15-2008
Quote:
Originally Posted by
mgig
Hello,
I run my pthread code on Linux with 4 processors. However, the speed up is only 2 times.
Stop right there. Post your /proc/cpuinfo before we proceed. I believe that may help answer some questions.
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LEARN ABOUT CENTOS
pthread
pthread.h(3HEAD) Headers pthread.h(3HEAD)
NAME
pthread.h, pthread - threads
SYNOPSIS
#include <pthread.h>
DESCRIPTION
The <pthread.h> header defines the following symbols:
PTHREAD_BARRIER_SERIAL_THREAD
PTHREAD_CANCEL_ASYNCHRONOUS
PTHREAD_CANCEL_ENABLE
PTHREAD_CANCEL_DEFERRED
PTHREAD_CANCEL_DISABLE
PTHREAD_CANCELED
PTHREAD_COND_INITIALIZER
PTHREAD_CREATE_DETACHED
PTHREAD_CREATE_JOINABLE
PTHREAD_EXPLICIT_SCHED
PTHREAD_INHERIT_SCHED
PTHREAD_MUTEX_DEFAULT
PTHREAD_MUTEX_ERRORCHECK
PTHREAD_MUTEX_INITIALIZER
PTHREAD_MUTEX_NORMAL
PTHREAD_MUTEX_RECURSIVE
PTHREAD_ONCE_INIT
PTHREAD_PRIO_INHERIT
PTHREAD_PRIO_NONE
PTHREAD_PRIO_PROTECT
PTHREAD_PROCESS_SHARED
PTHREAD_PROCESS_PRIVATE
PTHREAD_SCOPE_PROCESS
PTHREAD_SCOPE_SYSTEM
The types listed below are defined as described in <sys/types.h>. See types.h(3HEAD).
pthread_attr_t
pthread_barrier_t
pthread_barrierattr_t
pthread_cond_t
pthread_condattr_t
pthread_key_t
pthread_mutex_t
pthread_mutexattr_t
pthread_once_t
pthread_rwlock_t
pthread_rwlockattr_t
pthread_spinlock_t
pthread_t
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
SEE ALSO
sched.h(3HEAD), time.h(3HEAD), types.h(3HEAD), pthread_attr_getguardsize(3C), pthread_attr_init(3C), pthread_attr_setscope(3C),
pthread_cancel(3C), pthread_cleanup_pop(3C), pthread_cond_init(3C), pthread_cond_signal(3C), pthread_cond_wait(3C), pthread_con-
dattr_init(3C), pthread_create(3C), pthread_detach(3C), pthread_equal(3C), pthread_exit(3C), pthread_getconcurrency(3C), pthread_getsched-
param(3C), pthread_join(3C), pthread_key_create(3C), pthread_key_delete(3C), pthread_mutex_init(3C), pthread_mutex_lock(3C),
pthread_mutex_setprioceiling(3C), pthread_mutexattr_init(3C), pthread_mutexattr_init(3C), pthread_mutexattr_init(3C), pthread_mutex-
attr_gettype(3C), pthread_mutexattr_getprotocol(3C), pthread_once(3C), pthread_rwlock_init(3C), pthread_rwlock_rdlock(3C),
pthread_rwlock_unlock(3C), pthread_rwlock_wrlock(3C), pthread_rwlockattr_getpshared(3C), pthread_rwlockattr_init(3C), pthread_self(3C),
pthread_setcancelstate(3C), pthread_setspecific(3C), attributes(5), standards(5)
SunOS 5.10 9 Sep 2004 pthread.h(3HEAD)