SUN-3s talking to SUN-2s with 3COM boards

guy at sun.UUCP guy at sun.UUCP
Fri May 9 17:31:21 AEST 1986


> This code bypasses much of the normal TCP/IP code, for efficiency. ...
> The problem does not afflict normal TCP use because the TCP code in
> the kernel isn't nearly as fast.  It generates packets one at a time,
> rather than in bursts.

A clarification: it bypasses all of the TCP code, because NFS uses Sun RPC
with UDP, not TCP, as its transport mechanism.  (It does bypass much of the
UDP and IP code, as well.)

> Rather, under version 3.0 there is a parameter you can specify in the
> mount that gives a maximum block size.  You simply limit NFS to 2K
> blocks.

Note that this is also useful if you are mounting a file system from a
machine which is many gateways away from you.  The IP datagram containing
the UDP datagram containing NFS replies gets fragmented, as was pointed out
in the previous message; this causes problems sending the NFS reply along a
path involving several gateways.
-- 
	Guy Harris
	{ihnp4, decvax, seismo, decwrl, ...}!sun!guy
	guy at sun.arpa



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