jail process limits

[Kris Kennaway]

On Thu, May 22, 2008 at 03:26:13PM -0400, Vivek Khera wrote:
> While we're on the topic of jail resource limits, I think I'll ask my  
> question again...  I asked last month but got no response...
> 
> 
> I've got a jail server (FreeBSD 6.3/amd64) which runs a bunch of web  
> site development environments.  There is an apache or lighttpd running  
> in each jail as user httpd (same UID on base system and each jail).
> 
> On the jail host, I counted 231 processes owned by httpd.
> 
> If I try to start an application server (or any process) as user httpd  
> in one of the jails, it exits immediately with "Cannot fork: Resource  
> temporarily unavailable".  Even if I "su httpd" I get the same error  
> on any command I try to run such as "ls".  If I run the same on the  
> jail host, it has no problems.  The jail itself only has 34 processes  
> running.
> 
> On the jail host, the following is logged:
> 
> Apr 22 16:34:38 staging kernel: maxproc limit exceeded by uid 80,  
> please see tuning(7) and login.conf(5).

> Can anyone tell me where to look to find out what is limiting user  
> httpd from creating new processes inside the jail, and what exactly  
> that limit is?  More importantly, how to increase it.

I'd start by instrumenting the code path that leads to the above
kernel printf, to try and differentiate any possible causes.

Kris

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