From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ron Mercer <ron.mercer@qlogic.com>
Subject: Re: [net-next PATCH 3/3] qlge: Increase default TX/RX ring size to
	1024.
Date: Thu, 11 Jun 2009 16:21:59 -0700
Message-ID: <20090611232159.GA13392@linux-ox1b.qlogic.org>
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To: David Miller <davem@davemloft.net>
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> This is huge.  Even other aggressive NICs such as BNX2X only use 256
> ring entries per TX queue.
> 
> There is a point where increasing definitely hurts, because you're
> increasing the resident set size of the cpu, as more and more SKBs are
> effectively "in flight" at a given time and only due to the amount
> you're allowing to get queued up into the chip.
> 
> And with multiqueue, per-queue TX queue sizes should matter less at
> least to some extent.
> 
> Are you sure that jacking the value up this high has no negative side
> effects for various workloads?

Just drop this patch for now.  I looked at our spreadsheet and ran the
tests again and we see a (marginal) throughput increase that leveled off
at TXQ length of 1024.  In light of yours and Stephens comments I prefer
to revisit this issue.