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Date: Fri, 9 Nov 2007 16:09:06 -0800
From: "Matt Reimer" <mattjreimer@gmail.com>
To: net@freebsd.org
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Subject: Should syncache.count ever be negative?
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On a eight core machine running RELENG_7 I'm seeing TCP stalls,
sometimes lasting up to 60 seconds or so. While trying to track this
down I noticed that net.inet.tcp.syncache.count is negative. Should it
be possible for the count to go negative? Perhaps it indicates a race,
or the counter is wrongly being decremented twice?

Matt

# sysctl net.inet.tcp.syncache
net.inet.tcp.syncache.rst_on_sock_fail: 1
net.inet.tcp.syncache.rexmtlimit: 3
net.inet.tcp.syncache.hashsize: 512
net.inet.tcp.syncache.count: -97
net.inet.tcp.syncache.cachelimit: 15360
net.inet.tcp.syncache.bucketlimit: 30