pthread_create: cannot allocate memory
Giovanni P. Tirloni
gpt at tirloni.org
Thu Aug 18 16:29:45 GMT 2005
I coded a small echo server that creates a thread for every connection
it accepts. It works fine and then I decided to test how many threads it
could handle so I coded a stress.c client program that'd just create as
many connections as I asked without exchanging any data.
First I discovered the kern.threads.max_thread_per_proc limit that was
limiting it to 1500 threads. So I raised it and the max_group_per_proc
I also increased the NMBCLUSTERS limit to 65535 just in case.
What I've seen is that the server stops at 2400-2410 threads when I
ask strees.c to create 8k connections. top shows I still have 150MB of
Where should I look to raise this limit ? This is a CeleronM 1.3GHz
and 512MB of RAM.
Another behavior was that it creates 130 threads at once, waits, then
another 130 more. It varies 1-10 threads sometimes but usually this
inverval is constant. I think it might have something to do with the TCP
code doing some normal limitation but I've look at it.
Giovanni P. Tirloni / gpt at tirloni.org
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