kern/96268: [socket] TCP socket performance drops by 3000% if packets are split at the first byte

[Tom Judge]

The following reply was made to PR kern/96268; it has been noted by GNATS.

From: Tom Judge <tom at tomjudge.com>
To: bug-followup at FreeBSD.org, jost2345 at users.sourceforge.net
Cc:  
Subject: Re: kern/96268: [socket] TCP socket performance drops by 3000% if
 packets are split at the first byte
Date: Wed, 14 Jan 2009 19:31:11 -0600

 I have seen this issue on 7.0-RELEASE. 
 
 It seems to be related to the nagle algorithm being enable by default on 
 connections on the loop back interface.
 
 One application level work around is to set the TCP_NODELAY option on 
 the socket so that the nagle algorithem is disabled.
 
 This bug affects users of php java bridge as newer release talk to a JVM 
 over a tcp socket bound to localhost, and the typical packets passing 
 back and forward are very small.
 
 It is also possible to reproduce this bug using PHP 5.  I can attach 
 test scripts if required.
 
 Tom