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Date: Sat, 08 Dec 2012 00:07:24 +0100
From: bartels <bartels AT mailme DOT ath DOT cx>
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Subject: Re: Intermittent failures retrieving process exit codes
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On 12/07/2012 08:54 PM, Tom Honermann wrote:
>
> I recently was able to produce a very small test case that reproduces this issue reliably on some machines:

Your suspicion about a race condition may very well be correct: I can easily confirm the problem on both iron and virtual smp, but not on a 
single core virtual.

I have two instances of your test case running for half hour on the same core, without any problem: 30k cycles without hickup.

Apart from the immediate effect exposed by your script, I have reason to believe that the root cause also affects other running (smp) processes.

bartels

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