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Date: Mon, 12 Apr 2004 16:50:18 -0700 (PDT)
From: Julian Elischer <julian@elischer.org>
To: Tim Robbins <tjr@freebsd.org>
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cc: FreeBSD current users <current@freebsd.org>
Subject: Re: JKH project..
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On Tue, 13 Apr 2004, Tim Robbins wrote:

> On Sun, Apr 11, 2004 at 03:51:45PM -0700, Julian Elischer wrote:
> 
> > Junior kernel hacker project..
> > 
> > the fork syscall has to check the new PID against all exixting pids..
> > 
> > here's the current code.. when teh PID-space starts becoming
> > "fragmented.."  this starts to take "real time".
> [...]
> > with several thousand processes, forking a lot, this starts to take 
> > a 'noticable' amount of time.
> 
> I've been using a hashtable-based PID allocator for the last few months.
> I didn't have enough time to run any serious benchmarks, so I never
> committed it. If the amount of time is noticeable in your environment,
> would you mind trying the patch below?
> 
> > 
> > Suggestions welcome.. :-)
> 

Well what you've done seems to fit my definition of "improved"..

anyone got comments?

You are sure you have all the cases when session, (etc) code handles a
dead session leader etc.?


> 
>