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Date: Thu, 29 Jun 2006 01:40:50 -0700
From: Paul Jackson <pj@sgi.com>
To: Jay Lan <jlan@engr.sgi.com>
Cc: akpm@osdl.org, nagar@watson.ibm.com, balbir@in.ibm.com, csturtiv@sgi.com,
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Subject: Re: [Patch][RFC]  Disabling per-tgid stats on task exit in
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Jay wrote:
> The ENOBUFS i experienced in my testing would start to happen
> when exit rate at around 14000 exits/sec. While our fields confirmed
> that a 1000 threads exit/sec was a real, i have no reason to be
> concerned of 14000 exits/sec rate. ;)

Andrew wrote:
>1000 exits/sec/CPU can happen.  How many CPUs did that machine have?

Jay - what happens if we have 1024 CPUs (the current default config
for ia64/sn2)?

My naive expectation would be that the rate of exits/sec would go up as
the number of CPUs. In other words, I'd expect the exits/sec/CPU to be
a rough constant, slowly increasing over the years as the CPU clock
rate goes up.

So if current CPU technology can generate 1000 exits/sec, and if we
have 1024 CPUs then doesn't that mean we'd like to handle a million
exits/sec?

-- 
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj@sgi.com> 1.925.600.0401