From owner-freebsd-questions@freebsd.org  Sat Aug 29 06:14:41 2015
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Date: Fri, 28 Aug 2015 23:09:22 -0700 (PDT)
From: Dmitry Mikhailov <dmitry@pushware.net>
To: freebsd-questions@freebsd.org
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Subject: syncookie CPU load
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Doing a SYN flood test with FreeBSD on Xeon D (8 core) with syncookies enabled and the CPU load is around 20% (interrupts) at 150K pps. Is there any way reconfigure FreeBSD to bring this load down? Linux has a solution with netfilter synproxy which would not notice this low pps rate so I am wondering whether something similar is possible with FreeBSD? 

Dmitry