From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [tbench regression fixes]: digging out smelly deadmen.
Date: Thu, 30 Oct 2008 11:15:26 -0700
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Cc: "Rafael J. Wysocki" <rjw@sisk.pl>, Ingo Molnar <mingo@elte.hu>,
	Evgeniy Polyakov <s0mbre@tservice.net.ru>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
	David Miller <davem@davemloft.net>,
	Mike Galbraith <efault@gmx.de>,
	Andrew Morton <akpm@linux-foundation.org>
To: Evgeniy Polyakov <zbr@ioremap.net>
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Has anyone looked into the impact of port randomization on this benchmark.
If it is generating lots of sockets quickly there could be an impact:
  * port randomization causes available port space to get filled non-uniformly
    and what was once a linear scan may have to walk over existing ports.
    (This could be improved by a hint bitmap)

  * port randomization adds at least one modulus operation per socket
    creation. This could be optimized by using a loop instead.