Hi all,
I am working in a UNIX/C environment. I would like to understand more about MUTEX and Threads. Can someone explain me these
concepts and how they are related.
Vijay (2 Replies)
Is it possible that the function "pthread_cond_broadcast" block itself and the function "pthread_cond_wait" unblock in multi-threads programming ? The operating system is AIX 5.2, its maintenance level is : 5.2.0.4, VisualAge C++ 6.0.
Thanks (0 Replies)
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? ... (1 Reply)
Hello,
I run my pthread code on Linux with 4 processors. However, the speed up is only 2 times.
The code is about solving equation (G+s(i)C)z(i)=B*us(i), i=1,...,n. Here G,C are m*m matrix, B*us(i) is a m*1 vector and s(i) are n different numbers. I need to solve the equation n times to... (1 Reply)
I am trying to use mutex in my multi-tread project, but they don't seem to work.
I have created a simple demonstration of the problem. This is NOT how I would use a mutex, only a demonstration of the problem:
#include <stdio.h>
#include <pthread.h>
int main()
{
int val;
... (3 Replies)
Hi all,
I have a scenario where I need to use the mutex locks. The mutex locks are working fine, but sometimes I am getting into the dead lock situation.
Below is the summary of my code :
MUTEX LOCK
performTask();
MUTEX UNLOCK.
In some cases I get into the situation where... (2 Replies)
Using pthreads is there a way to determine how many threads are waiting on a locked resource? I mean, once a shared resource is protected using e.g. pthread_rwlock_t or pthread_mutex_t one thread grabs the lock and other threads will go to sleep waiting for the resource to be available again. Is... (0 Replies)
Hi,
I wrote the following program to understand mutexes. If I run the program , number of threads is shown as zero, even after creating one thread. When running with gdb, it works fine.
The function process is used to update global variable (used to keep track of threads). It looks like the... (2 Replies)