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Cc: src-committers@FreeBSD.org, d@delphij.net,
	Peter Jeremy <peterjeremy@acm.org>, svn-src-all@FreeBSD.org,
	Xin LI <delphij@FreeBSD.org>, svn-src-head@FreeBSD.org
Subject: Re: svn commit: r198848 - head/bin/ps
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On Fri, 13 Nov 2009, Bruce Evans wrote:

>>> Just print %CPU in %4.0f format when it is >= 99.5 (or whatever rounds to 
>>> 100.0).  This works up to 999.5 %CPU.
>> 
>> Actually, %4.0f works up to 9999.5 %CPU because there's no '.' in the 
>> result.  I think this is an excellent solution.  And since FreeBSD 
>> currently has a hard limit of 64 CPUs, it's unlikely to be exceeded for a 
>> while.
>
> Oops.

With 128-thread hardware just around the corner, we should be working to scrub 
assumption of 32 or 64 core limits wherever we find them.  I don't know what 
the next "reasonable" limit is, perhaps 1024, but arrays indexed by MAXCPU are 
becoming decreasingly useful in that light.  The dynamic per-CPU stuff for the 
kernel addresses some but not all of these problems.

Robert N M Watson
Computer Laboratory
University of Cambridge