linux最大线程数及最大进程数,Linux中每个进程的最大线程数

#include

#include

#include

#include

// this prevents the compiler from reordering code over this COMPILER_BARRIER

// this doesnt do anything

#define COMPILER_BARRIER() __asm__ __volatile__ (\"\" ::: \"memory\")

sigset_t _fSigSet;

volatile int _cActive = 0;

pthread_t thrd[1000000];

void * thread(void *i)

{

int nSig, cActive;

cActive = __sync_fetch_and_add(&_cActive, 1);

COMPILER_BARRIER(); // make sure the active count is incremented before sigwait

// sigwait is a handy way to sleep a thread and wake it on command

sigwait(&_fSigSet, &nSig); //make the thread still alive

COMPILER_BARRIER(); // make sure the active count is decrimented after sigwait

cActive = __sync_fetch_and_add(&_cActive, -1);

//printf(\"%d(%d) \", i, cActive);

return 0;

}

int main(int argc, char** argv)

{

pthread_attr_t attr;

int cThreadRequest, cThreads, i, err, cActive, cbStack;

cbStack = (argc > 1) ? atoi(argv[1]) : 0x100000;

cThreadRequest = (argc > 2) ? atoi(argv[2]) : 30000;

sigemptyset(&_fSigSet);

sigaddset(&_fSigSet, SIGUSR1);

sigaddset(&_fSigSet, SIGSEGV);

printf(\"Start\\n\");

pthread_attr_init(&attr);

if ((err = pthread_attr_setstacksize(&attr, cbStack)) != 0)

printf(\"pthread_attr_setstacksize failed: err: %d %s\\n\", err, strerror(err));

for (i = 0; i < cThreadRequest; i++)

{

if ((err = pthread_create(&thrd[i], &attr, thread, (void*)i)) != 0)

{

printf(\"pthread_create failed on thread %d, error code: %d %s\\n\",

i, err, strerror(err));

break;

}

}

cThreads = i;

printf(\"\\n\");

// wait for threads to all be created, although we might not wait for

// all threads to make it through sigwait

while (1)

{

cActive = _cActive;

if (cActive == cThreads)

break;

printf(\"Waiting A %d/%d,\", cActive, cThreads);

sched_yield();

}

// wake em all up so they exit

for (i = 0; i < cThreads; i++)

pthread_kill(thrd[i], SIGUSR1);

// wait for them all to exit, although we might be able to exit before

// the last thread returns

while (1)

{

cActive = _cActive;

if (!cActive)

break;

printf(\"Waiting B %d/%d,\", cActive, cThreads);

sched_yield();

}

printf(\"\\nDone. Threads requested: %d. Threads created: %d. StackSize=%lfmb\\n\",

cThreadRequest, cThreads, (double)cbStack/0x100000);

return 0;

}