Date: Mon, 2 Feb 2004 14:10:19 -0800 (PST) From: Craig Rodrigues <rodrigc@crodrigues.org> To: freebsd-threads@FreeBSD.org Subject: Re: kern/43887: abnormal CPU useage when use pthread_mutex Message-ID: <200402022210.i12MAJx4057870@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
The following reply was made to PR kern/43887; it has been noted by GNATS.
From: Craig Rodrigues <rodrigc@crodrigues.org>
To: freebsd-gnats-submit@freebsd.org
Cc: t_fisher@163.com
Subject: Re: kern/43887: abnormal CPU useage when use pthread_mutex
Date: Mon, 2 Feb 2004 17:05:28 -0500
Hi,
I don't think that this PR is very meaningful, and should be closed.
This PR basically complains about the following code
consuming too much CPU if you take out the usleep().
=====================================================================
#include <unistd.h>
#include <pthread.h>
#include <errno.h>
int main(int argc,char** argv)
{
pthread_mutex_t mutex;
long i,j;
j =0;
pthread_mutex_init(&mutex,NULL);
while(1)
{
pthread_mutex_lock(&mutex);
i = j*j;
j++;
pthread_mutex_unlock(&mutex);
printf("i=%ld\n",i);
if(usleep(800)== -1)
printf("usleep fail. %s",strerror(errno));
}
return 0;
}
=====================================================================
Well, this code isn't doing too much, except for spinning
in a tight loop. I think this PR should be closed.
--
Craig Rodrigues
rodrigc@crodrigues.org
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200402022210.i12MAJx4057870>