Re: [Patch 1/1] init: Provide a kernel start parameter to increasepid_max v2

[Mike Travis]

Rik van Riel wrote:
> On 04/21/2010 12:59 PM, Hedi Berriche wrote:
> > On Wed, Apr 21, 2010 at 10:20 Alan Cox wrote:
> > |>  of 32k will not be enough.  A system with 1664 CPU's, there are 
> > 25163 processes
> > |>  started before the login prompt.  It's estimated that with 2048 
> > CPU's we will pass
> > |
> > | Is that perhaps the bug not the 32K limit?
> >
> > Doubt it: I just checked on an *idle* 1664 CPUs system and I can see 
> > 26844
> > tasks, all but few being kernel threads.
>
> That is 15 kernel threads per CPU.
>
> Reducing the number of kernel threads sounds like a
> useful thing to do.

I'm doing more research but all the udev modprobes seem to spawn
quite a few tasks.  And even though they go away, when the pid
pool is limited, I'm guessing many of them are waiting.

On the last test I did yesterday, the pid # was up in the 77000
range at the login prompt (I started the 1664 cpu system with
pid_max=128k).
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