tech-net: Re: Default minimum TCP MSS

Subject: Re: Default minimum TCP MSS
To: Darren Reed <darrenr@reed.wattle.id.au>
From: Darren Reed <darrenr@reed.wattle.id.au>
List: tech-net
Date: 07/07/2001 23:15:36

Further to this, I think the patch below should also be used...
although I suspect that at 512 it only uses 2 mbufs in a cluster
to store 512 bytes whereas 536 would waste 232 bytes?

Darren

Index: tcp.h
===================================================================
RCS file: /cvsroot/syssrc/sys/netinet/tcp.h,v
retrieving revision 1.13
diff -c -r1.13 tcp.h
*** tcp.h	2001/05/26 21:40:55	1.13
--- tcp.h	2001/07/07 13:09:36
***************
*** 90,100 ****
  
  /*
   * Default maximum segment size for TCP.
!  * With an IP MSS of 576, this is 536,
!  * but 512 is probably more convenient.
!  * This should be defined as min(512, IP_MSS - sizeof (struct tcpiphdr)).
   */
! #define	TCP_MSS		512
  
  #define	TCP_MAXWIN	65535	/* largest value for (unscaled) window */
  
--- 90,98 ----
  
  /*
   * Default maximum segment size for TCP.
!  * With an IP MSS of 576, this is 536 [RFC1122:4.2.2.6],
   */
! #define	TCP_MSS		536
  
  #define	TCP_MAXWIN	65535	/* largest value for (unscaled) window */