Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!wuarchive!uunet!mcsun!ukc!acorn!unipalm!ian
From: ian@unipalm.uucp (Ian Phillipps)
Newsgroups: comp.protocols.tcp-ip.ibmpc
Subject: Re: PC-NFS performance
Message-ID: <1991Mar1.151130.6998@unipalm.uucp>
Date: 1 Mar 91 15:11:30 GMT
References: <448@newmedia.UUCP>
Organization: Unipalm Ltd., Cambridge, England
Lines: 26

jim@newmedia.UUCP (Jim Beveridge) writes:

>I am running PC-NFS v3.0.1 hooked up to a Sun 3/60 server.
>The problem is that the write performance is awful -- it does
>pretty well reading, ...

>Is this just a problem with PC-NFS?  Is there a parameter that
>I didn't tune?  How can I adjust rsize and wsize?

The problem (flames coming in if I'm wrong, no doubt) is that NFS is a
synchronous protocol, so the write has to be complete before the NFS call is
finished.  For a Unix client, this doesn't matter, since the kernel handles
the asynchonosity (is that the word?) itself.

BUT - DOS is also synchronous, so you have a wait on your hands.
As far as I know, the write size is fixed at 1K.

Some other implementations of NFS client for DOS get round this problem by
de-synchronising themselves - the only one I know that does this is
Interdrive 1.1 from FTP.

The other alternative is to add a Prestoserve board (from Legato
Systems) to your Sun, which is specifically aimed at this problem: it's
an intelligent disk cache which acknowledges the NFS write before the
info actually hits the disk, and retains security by holding the disk
info in non-volatile RAM.