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From: Hubertus Franke <frankeh@watson.ibm.com>
Reply-To: frankeh@watson.ibm.com
Organization: IBM Research
To: Guest section DW <dwguest@win.tue.nl>
Subject: Re: Fwd: [Lse-tech] get_pid() performance fix
Date: Thu, 7 Mar 2002 18:14:10 -0500
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Cc: Rusty Russell <rusty@rustcorp.com.au>, rajancr@us.ibm.com,
        linux-kernel@vger.kernel.org, lse-tech@lists.sourceforge.net
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On Thursday 07 March 2002 02:46 pm, Guest section DW wrote:
> On Thu, Mar 07, 2002 at 02:07:38PM -0500, Hubertus Franke wrote:
> > On Thursday 07 March 2002 09:54 am, Guest section DW wrote:
> > > On Thu, Mar 07, 2002 at 09:35:09AM -0500, Hubertus Franke wrote:
> > > ...
> > >
> > > Long ago I submitted a patch that changed the max pid from 15 bits to
> > > 24 or 30 bits or so. (And of course removed the inefficiency noticed
> > > by some people in the current thread.)
> >
> > I don't think that will solve the N^2 problem
>
> Do you understand "inefficiency"? And "remove"?


I do, what's your point ?
I haven't seen your patch picked up....

I do understand that when you occasionally get into this scenario
of the loop that particularly for large thread counts this stalls the system
for seconds (say 30, with the tasklock held).


-- 
-- Hubertus Franke  (frankeh@watson.ibm.com)
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