From owner-freebsd-hackers@FreeBSD.ORG  Tue Sep 20 19:19:52 2011
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Date: Tue, 20 Sep 2011 22:19:49 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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To: Alexander Motin <mav@FreeBSD.org>
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Cc: hackers@FreeBSD.org
Subject: SW_WATCHDOG vs new eventtimer code
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Alexander,

just want to check with you first if the following makes sense.
I use SW_WATCHDOG on one of the test machines, which was recently updated to
from stable/8 to head.  Now it seems to get seemingly random watchdog events.
My theory is that this is because of the eventtimer logic.
If during idle period we accumulate enough timer ticks and then run all those
ticks very rapidly, then the SW_WATCHDOG code may get an impression that it was
not patted for many real ticks.
Not sure what would be the best way to make SW_WATCHDOG happier/smarter.

-- 
Andriy Gapon