Newsgroups: comp.protocols.nfs
Path: utzoo!utgpu!news-server.csri.toronto.edu!utpsych!jarvis
From: jarvis@psych.toronto.edu (Brian Jarvis)
Subject: NFS Problems
Message-ID: <1991Feb18.165842.12709@psych.toronto.edu>
Sender: jarvis@psych.toronto.edu (Brian Jarvis)
Organization: Department of Psychology, University of Toronto
Date: Mon, 18 Feb 91 16:58:42 GMT

I'm in need of some advice...

I've got a number of machines, some lowly 4.77 MHz 8086's, others are
20 MHz 386's, all equipped with WD8003e controllers and Beame & Whiteside
NFS software (Ver. 2.10).

I've found that, for optimal through-put, the PC's should be configured
to read in blocks of 4096 bytes, but writing should only be done in
512 byte blocks, the smallest possible.  With these settings, reading
files across the network from the server can be done at about 10K/s, but
writing still chugs at a mere 0.3K/second.  If I raise the write block
parameter to 4096 bytes, this number shrinks to 0.1K/second.  These
tests were taken when traffic on the network was relatively light.

The way the ethernet is installed in our building is somewhat brain-damaged,
I do confess.  It's easy for me to criticize:  I wasn't here when it was
installed!  B{)  I do, however, have to live with it...

The above numbers came from my PC on the 4th floor of our building.  The
packets from the server have to travel along the ground floor (where the
server is located), through a repeater, up to the 4th floor to a router
which then pushes packets out onto 5 different loops.  I'm on one of
these loops.  Other machines connected to the network between the repeater
and the server do not have any difficulty getting excellent through-put,
writing and reading.  Machines after the repeater and router are all
equally sluggish.  All of this would seem to point to problems with
the repeater and router; I haven't yet been able to plant a machine between
the two to see if I can nail it down further, but we'll see...

The part that confuses me most is that telnet and rlogin operations are
not affected.  I can read news and mail from the server with bwktel and
NCSA telnet from my same PC without the slightest hint of sluggishness.
"ftp" through-put exceeds 50K/second.  Go figure.

Now the questions:

1)  Does anyone have a clue where I should be concentrating my efforts?
    I've been spending quite a bit of time checking all items I could,
    but it's clear now that I'm only thrashing.  Pointers are welcome.

2)  Has this ever happened to anyone else?  How did they fix it?

3)  Does anyone have pointers to any sort of preferred network monitoring
    software or hardware?  I've been playing with "NFSWATCH 3.0".  Is
    there any sort of recommended ethernet sniffer (the cheaper the better)
    that I could acquire to help debug this and other ethernet problems?

4)  Is anyone out there actually using Beame & Whiteside NFS software?
    Sometimes I get the impression we're the only ones... B{/

Thanks!

Brian

-- 

Brian A. Jarvis,          Rm. 4026, Sidney Smith Hall, Dept. of Psychology,
jarvis@psych.toronto.edu  University of Toronto, Toronto, Ontario, Canada
System Administrator      M5S 1A1  (416) 978-3948