On Jan 6, 2006, at 2:41 PM, Andy Huebner wrote:

How would I determine what the per-process thread limit is?  Your
suggestion of a thread limitation seems to fit the known facts.

Andy - Here's some info from my AIX notes...

Threads, maximum number                 The programming limits are
defined in
                                        /usr/include/pthreads.h and
                                        /usr/include/sys/limits.h as:
                                         #ifdef _LARGE_THREADS
                                         #define PTHREAD_THREADS_MAX
32767
                                         #else
                                         #define PTHREAD_THREADS_MAX
512
                                        These defines prevail in AIX
4.3, 5.1,
                                        and 5.2.  AIX redbook
"Developing and
                                        Porting C and C++
Applications on AIX"
                                        says that 512 is a
sufficient number for
                                        most multi-threaded
applications,
                                        regardless of 32- or 64-bit
applications.
                                        If pthread_create() goes
over the limit,
                                        errno EAGAIN (11) will occur.
                                        Note that the creation of
Pthreads
                                        consumes the process heap.
                                        I'm not aware of any system
file
                                        configuration option which can
                                        artificially limit the
number of threads
                                        per process.

I verified the behavior with a programming test.
There's no telling what value the AIX TSM server may have been
compiled with.
Again, ANR messages and AIX Error Log entries should say what the
issue is.

   Richard Sims