On Sun, 21 Oct 2007, Ruediger Pluem wrote:
What is your setting for ThreadsPerChild?
On my Linux each thread consumes 8MB of virtual memory (I assume for
stack and other thread private data) as shown by pmap. This can sum
up to a large amount of memory.
This is due to linux libc setting the thread stack size using the
stack resource limit. We have the following in our apache httpd
startup script:
# NPTL (modern Linux threads) defaults the thread stack size to the setting
# of your stack resource limit. The system-wide default for this is 8MB,
# which is waaay exaggerated when running httpd.
# 512kB should be more than enough (AIX manages on 96kB, Netware on 64kB).
ulimit -s 512
We didn't bother with trying to lower it more, but I've run the same
httpd config on IBM AIX 5.1 with the default 96kB thread stack size
without problems.
This could probably be worked around in httpd/APR by calling setrlimit
before starting the threads, however I think it's probably better to
just document this Linux thread bogosity and let vendors fix their
httpd startup scripts though.
/Nikke
--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Niklas Edmundsson, Admin @ {acc,hpc2n}.umu.se | [EMAIL PROTECTED]
---------------------------------------------------------------------------
No boom now. Boom tomorrow...there's ALWAYS a boom tomorrow...BOOM!
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
