Re: limits.conf/stacksize doesn't seem to work?

From: Larry Rosenman <ler_at_lerctr.org>
Date: Fri, 15 Jul 2022 22:34:38 UTC 
On 07/15/2022 5:32 pm, Mark Johnston wrote:
> On Fri, Jul 15, 2022 at 05:26:09PM -0500, Larry Rosenman wrote:
>> On 07/15/2022 5:24 pm, Mark Johnston wrote:
>> > On Fri, Jul 15, 2022 at 05:21:27PM -0500, Larry Rosenman wrote:
>> >> On 07/15/2022 5:18 pm, Mark Johnston wrote:
>> >> > On Fri, Jul 15, 2022 at 05:04:18PM -0500, Larry Rosenman wrote:
>> >> >> I'm using the following kernel config:
>> >> >> [...]
>> >> >> and the following login.conf:
>> >> >> [...]
>> >> >> bacula_dir:\
>> >> >> 	:stacksize-max=68719476736:\
>> >> >> 	:stacksize-cur=68719476736:\
>> >> >> 	:tc=daemon:
>> >> >> [...]
>> >> >> I've updated my (ler) password entry to reference bacula_dir:
>> >> >> ler:<elided>:1001:1001:bacula_dir:0:0:Larry
>> >> >> Rosenman:/home/ler:/usr/local/bin/zsh
>> >> >>
>> >> >>
>> >> >> when I ssh in, the stacklimit is still:
>> >> >> โฏ ulimit -H -s
>> >> >> 2097152
>> >> >
>> >> > What is the value of the kern.maxssiz sysctl on this system?
>> >> >
>> >> >> ler in ๐ŸŒ borg in sys/amd64/conf๐Ÿ”’ on ๎‚  ler/freebsd-main-changes:main on
>> >> >> โ˜๏ธ  (us-east-1)
>> >> >> โฏ ulimit -S -s
>> >> >> 2097152
>> >> >>
>> >> >> ler in ๐ŸŒ borg in sys/amd64/conf๐Ÿ”’ on ๎‚  ler/freebsd-main-changes:main on
>> >> >> โ˜๏ธ  (us-east-1)
>> >> >> โฏ
>> >> >>
>> >> >> Where does this number come from?  What am I missing here?
>> >> >
>> >> > The stack limit cannot be set to an arbitrarily large number.  It will
>> >> > silently be clamped to maxssiz.
>> >>
>> >> โฏ sysctl kern.maxssiz
>> >> kern.maxssiz: 2147483648
>> >
>> > Then what you're seeing is expected.  The kernel is clamping the stack
>> > segment limit to 2GB.
>> 
>> I assume this is the default for MAXSSIZ?  and if I change that in the
>> kernel config, it will
>> allow bigger?  Where is this default defined?
> 
> The default value is platform dependent.  On amd64 it's 512MB, so I'm
> not sure where your value is coming from.  It's defined in a header.
> You can set it in the kernel configuration, or as a tunable or sysctl.

ok, so I had (back when, heaven only knows) set it in /boot/loader.conf:
kern.maxssiz="2147483648"

thank you.

-- 
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 214-642-9640                 E-Mail: ler@lerctr.org
US Mail: 5708 Sabbia Dr, Round Rock, TX 78665-2106