From: David Miller <davem@davemloft.net>
To: wenji@fnal.gov
Cc: netdev@vger.kernel.org, akpm@osdl.org, linux-kernel@vger.kernel.org
Subject: Re: Bug 7596 - Potential performance bottleneck for Linxu TCP
Date: Wed, 29 Nov 2006 17:01:41 -0800 (PST) [thread overview]
Message-ID: <20061129.170141.23017532.davem@davemloft.net> (raw)
In-Reply-To: <HNEBLGGMEGLPMPPDOPMGKEAJCGAA.wenji@fnal.gov>
The delays dealt with in your paper might actually help a highly
loaded server with lots of sockets and threads trying to communicate.
The packet processing delays caused by the scheduling delay paces the
TCP sender by controlling the rate at which ACKs go back to that
sender. Those ACKs will go out paced to the rate at which the
sleeping TCP receiver gets back onto the cpu, and this will cause the
TCP sender to naturally adjust to the overall processing rate of the
receiver system, on a per-connection basis.
Perhaps try a system with hundreds of processes and potentially
hundreds of thousands of TCP sockets, with thousands of unique sender
sites, and see what happens.
This is a similar topic like TSO, where we are trying to balance the
gains from batching work from the losses of gaps in the communication
stream.
prev parent reply other threads:[~2006-11-30 1:01 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <HNEBLGGMEGLPMPPDOPMGKEAJCGAA.wenji@fnal.gov>
2006-11-29 23:27 ` [Changelog] - Potential performance bottleneck for Linxu TCP Wenji Wu
2006-11-29 23:28 ` [patch 1/4] " Wenji Wu
2006-11-29 23:29 ` [patch 2/4] " Wenji Wu
2006-11-29 23:30 ` [patch 3/4] " Wenji Wu
2006-11-29 23:31 ` [patch 4/4] " Wenji Wu
2006-11-30 0:53 ` [patch 1/4] " David Miller
2006-11-30 1:08 ` Andrew Morton
2006-11-30 1:13 ` David Miller
2006-11-30 6:04 ` Mike Galbraith
2006-11-29 23:36 ` [Changelog] " Martin Bligh
2006-11-29 23:42 ` Bug 7596 " Andrew Morton
2006-11-30 6:32 ` Ingo Molnar
2006-12-19 18:37 ` Stephen Hemminger
2006-12-19 23:52 ` Herbert Xu
2006-12-20 2:55 ` David Miller
2006-12-20 5:11 ` Stephen Hemminger
2006-12-20 5:15 ` David Miller
2006-11-30 1:01 ` David Miller [this message]
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