How to know number of user threads from /proc

[Dave Hylands]

Hi Kris,

On Sun, Feb 26, 2012 at 3:15 AM, emani murali <murali132 at gmail.com> wrote:
> Hi,
>  I'm running a multithreaded program in OpenMP on linux to study CPU
> overloading. As the subject says, I need to know the number of threads this
> program creates (assuming in this case, number of threads in this program is
> same as the number of user threads) from the information kernel provides.
>
> I'm looking something similar to run-queue length from "sar -q 0" that gives
> me exact picture of number of user threads. From the implementation of sar,
> I found that this information is fetched from /proc filesystem.
>
> So is there anyway that /proc fs gives me the number of threads running in
> the system, apart from /proc/cpuinfo that gives me a static information of
> existing CPUs.

There is a directory in /proc/PID/task for each thread contained
within a process.

-- 
Dave Hylands
Shuswap, BC, Canada
http://www.davehylands.com