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To: Bill Fenner <fenner@parc.xerox.com>
cc: Chris Csanady <ccsanady@friley01.res.iastate.edu>, hackers@FreeBSD.ORG
Subject: Re: TCP/IP bug? Unnecessary fragmentation... 
In-reply-to: Your message of "Wed, 25 Jun 1997 13:13:43 PDT."
             <97Jun25.131348pdt.177513@crevenia.parc.xerox.com> 
Date: Thu, 26 Jun 1997 16:54:03 +0900
From: Kenjiro Cho <kjc@csl.sony.co.jp>
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Bill Fenner wrote:
>> Kenjiro Cho <kjc@csl.sony.co.jp> wrote:
  >I think, considering the wide use of TCP, the socket layer should try
  >to call tcp_usr_send all at once when possible.

>> That would be going backwards, to some extent.  Van Jacobson wrote
>> in a 1988 message about upping TCP stack performance:

Hmmm, was the Nagle algorithm already implemented back then?

The modified sosend ends up with a long delay when divided chunks
trigger the Nagle Algorithm.
It seems worse than the possible gain by parallelism.

--kj

---
Kenjiro Cho
Sony Computer Science Laboratory Inc.