From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: RFC: Nagle latency tuning
Date: Tue, 09 Sep 2008 16:36:49 +0200
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Cc: Rick Jones <rick.jones2@hp.com>, Netdev <netdev@vger.kernel.org>
To: Chris Snook <csnook@redhat.com>
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In-Reply-To: <48C6052D.2080203@redhat.com> (Chris Snook's message of "Tue, 09 Sep 2008 01:10:05 -0400")
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Chris Snook <csnook@redhat.com> writes:
>
> I'd like to know where the 40 ms magic number comes from. 

>>From TCP_ATO_MIN

#define TCP_ATO_MIN     ((unsigned)(HZ/25))

> That's the
> one that really hurts, and if we could lower that without doing
> horrible things elsewhere in the stack, 

You can lower it (with likely some bad side effects), but I don't think it 
would make these apps very happy in the end because they likely want
no delay at all.

-Andi