lkml.org 
[lkml]   [2005]   [May]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: NPTL: stack limit limiting number of threads
On 5/13/05, Jakub Jelinek <jakub@redhat.com> wrote:
> On Fri, May 13, 2005 at 08:02:48PM -0400, Ritesh Kumar wrote:
> > Thanks for your reply. I actually went ahead after getting your
> > mail and coded up a small program to check the stack limit
> > deliberately. The program is shown inline.
> >
> > #include <stdio.h>
> >
> > #define BUF_SIZE 1024000
> >
> > void recurse(int n){
> > char ch[BUF_SIZE];
> > if(n<=0)
> > return;
> > else
> > recurse(n-1);
> > }
> >
> > int main(argc, argv)
> > int argc;
> > char **argv;
> > {
> > if(argc!=2){
> > printf("Usage: %s <n (megabytes)>\n", argv[0]);
> > return 1;
> > }
> > printf("Checking for %dMB\n", atoi(argv[1]));
> > recurse(atoi(argv[1]));
> > }
> >
> > Its a fairly crude way to find out the actual stack limit. Basically,
> > the resurse function recurses each time allocating ~1MB of space on
> > the stack. The program segfaults exactly at the ulimit -s value of
> > stack size on both linux and freebsd. So it does seem that the ulimit
> > -s is the value of stack limit used on FreeBSD.
>
> For the main stack sure. But now try to call that recurse in
> some other thread.
>
> Jakub
>

Oh great... I see your point now. I called the same recurse in an
alternative thread and found the limit to be 8M on Linux ( and Mac OS
X (Panther)) but around 1MB on FreeBSD. Thanks for the clarification!

Ritesh

--
http://www.cs.unc.edu/~ritesh/
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-05-14 03:00    [W:0.048 / U:1.988 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site