Re: mod_authn_file + low ThreadStackSize = oops

[Chris Darroch <ch...@pearsoncmg.com>]

Eric Covener wrote:

>> I'd set my ThreadStackSize really low, to 64 KB, and while that usually
>> lets you run without trouble
> 
> I was just about to document that _lowering_ the stack size with
> ThreadStackSize is unreliable since the underlying call used only sets
> a _minimum_ stack size, not an actual one.
> 
> Did you have any extenuating circumstances (old linux, alternate
> thread library, ulimit -s already set below 128?)

   Just a number of old Linux (but still NPTL) 32-bit boxes; that's the main
reason.  I'd seen this and some similar postings over the years and found
we could squeeze more threads in if we used, say, 128 KB in production
and 64 KB in dev for ThreadStackSize:

http://mail-archives.apache.org/mod_mbox/httpd-dev/200904.mbox/%3cPine.GSO.4.64.0904021650190.28858@hatchepsut.acc.umu.se%3e

   However ... I would certainly in interested in a clear accounting
of what, precisely, recent NPTL versions are doing with the
pthread_attr_setstacksize() setting and if changes from the (relatively
large) default value are useful or not.

Chris.

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