Ubuntu 11.04 Kernel Configurations

[Scott Ritchie]

On 03/26/2011 11:21 AM, Steve Langasek wrote:
> On Fri, Mar 25, 2011 at 07:05:00PM -0600, Tim Gardner wrote:
>>> Perhaps this is an appropriate time to ask, since I've been trying to
>>> ask for months now in mailing list/IRC but never apparently to the right
>>> person...
> 
>>> Can the kernel team please raise the hard limit for file descriptors
>>> (but keep the soft limit)?
> 
>>> https://bugs.launchpad.net/bugs/663090
> 
>>> I'm having real applications break from this, and the change shouldn't
>>> affect any app that doesn't request it manually.
> 
>> The initial hard limit value is not a CONFIG option, so the only way
>> it can be changed is by carrying a patch in the kernel, something I
>> would prefer not to do. This is the macro that initializes the hard
>> limit:
> 
>> include/linux/fs.h:#define INR_OPEN 1024                /* Initial
>> setting for nfile rlimits */
> 
>> What is the issue with having upstart set this limit early in the
>> boot cycle? Won't all new processes inherit the modified limit?
> 
> upstart currently has no provisions for configuring system-wide default
> ulimits.  The kernel, on the other hand, does.  If the defaults in the
> kernel are wrong for the system, that should be remedied there (both
> upstream and in Ubuntu).  Architecturally, I can see no reason why upstart
> should be setting this - if upstart is patched to set the ulimits, it will
> only be as a workaround for wrong values in the kernel.
> 

I'm really hoping this doesn't devolve to a situation where no component
wants to own a patch, and thus the problem goes unfixed for another year.

-Scott Ritchie