Subject: Re: increase default for number of files descriptors per process (was Re: Speeding up "pstat -T")
To: Andrew Brown <atatat@atatdot.net>
From: Perry E. Metzger <perry@piermont.com>
List: tech-kern
Date: 10/05/2003 18:57:18
Andrew Brown <atatat@atatdot.net> writes:
> >BTW, I've been wondering about a lot of our limits for some time. I
> >think that perhaps our kernels should compute them at boot time based
> >on available resources rather than forcing a "one size fits all" on
> >everyone. A machine with 4G of physical memory probably can afford to
> >let user processes have a bit of a larger default stack size than a
> >machine with 4M of memory, right?
> 
> two things.
> 
> (1) that sounds reasonable, but in practice, how many applications do
> you use that actually run up against the default soft limit of two
> megs?

Not often, but often enough. I came across problems with file
descriptor limits last week. I hit data size problems and stack size
problems every once in a while.

> (2) i have plans to eliminate the hard limit entirely (at least after
> an exec), so raising MAXSSIZ depending on memory detected at boot may
> also become a moot point.

Don't we want the hard limits for machines with potentially hostile
users?

Perry