thread limit question

[Kevin D. Clark]

Bryan Kate <bryankate at metrobility.com> writes:

> > Let's cut to the chase here:  are you creating detached threads?  Can
> > this work in your environment?  Doing this would probably allow you to
> > create a lot more threads.
> 
> yes, my threads are detached.

OK, good.

> > Note: if you have to create *a lot* of threads all the time, it might
> >       be worthwhile to create your own thread-pool.
> 
> i am creating a few pools, it is just that i need to support ALOT of
> devices, so my pools might be 100+ threads.  i dont need thousands, but
> maybe more than 255...
> 
> i dont see what the problem is, pthread_create returns 11 on thread 255,
> and if i do a perror on it, it just says Success... it isnt returning
> EAGAIN, indicating that i hit PTHREAD_THREADS_MAX (which is set at
> 16000+), and my ulimit on processes is 4093....
> 
> i am beginning to think there is another setting somewhere (the shell or
> in login?) that allows a limitation on processes. i just cant find it.

I just wrote a little program that creates 1000 detached threads.  It
runs fine on Linux.  This jives with my general experience of Linux --
I can create lots of threads when I need them.  "255" is not generally
a limit I am familiar with -- this is way too low.

Ideas: are you setting big thread stack sizes?  
       (so big that you overwhelm the stack?)

        are you compiling with -D_REENTRANT and linking with -lpthread ?


Can you provide us with a small test program that exhibits this behavior?

Regards,

--kevin
-- 
"We have to believe in free will. We've got no choice."
 --Bashevis Singer