treval@runxtsa.runx.oz.au (Trevor Luker) (10/05/89)
Hi,
A summary of responses to the question:
Sequent Machines - what are their strengths and weaknesses ?
Some time ago I put a message in this newsgroup regarding the Sequent
Symmetry machines. Based on the responses that I received, I prepared
a summary for the company management. The relevant sections of the
report are contained below. It makes interesting reading...
[ Any mistakes or mis-quotations are my fault, please excuse me ]
Thanks for all the help,
treval
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From: Trevor Luker (ISD 2238)
Subject: A summary of responses about the Sequent machines received
from USENET, with emphasis on support and growth potential.
Replies were received from (among others) :-
1) Patrick Wolfe System Manager, Kuck & Associates
2) Rich Kulawiec University of Colorado at Boulder
3) Carl S. Gutekunst Pyramid Corporation
4) Jesse Furqueron Sr. Software Engineer, VISystems
5) Andy Behrens Burlington Coat, Lebanon NH
6) John OBrien Bellcore
The questions and the responses from the above people are listed
below:-
Q) What are your experiences with bug-fixes and customer-support?
1. They are very good. Their machines have a mean time between
failure of over 1-1/2 years ... and we've had them [Field
Service] out once in the 3-1/2 years I've been here, to replace
a tape drive ...
2. ... I can't tell you much about their field service, because
the only time we ever saw them in 3 1/2 years was when they came
to install more processors ... Sequent's response to "critical"
bugs [In the OS] has been outstanding.
3. The hardware is exceptionally reliable, so you won't have much
use for hard-ware support. Software support is said to be
terrible; they won't admit they have bugs, and have to be
publically flogged into fixing them.
4. After almost a calender year of running [3] sequents, the number
of times we have been down because of hardware/software failures
you can count on both hands ... excellent support people -
[minor] bugs can take a while to get fixed (3-4 months), major
bugs usually within a week and most of that is in diagnosis.
5. Customer support and field service are outstanding. Software
support is good (they fix the bugs, but it sometimes takes them
a while to do so).
6. Very responsive! Bug fixes have been shipped promptly.
Customer support is great ...
Q) Does the [Sequent] architecture "scale" correctly, ie does
performance increase linearly with the number of processors
added?
1. Not linearly, but close. The small cabinet can handle up to 10
386's, and the large up to 30.
2. It's about as straightline as you're likely to see.
3. It scales beautifully if you stay CPU bound. UUNet, as a
counter example, is I/O bound; they have 10 CPUs now, and
adding more would not increase system throughput at all.
4. yes! As far as speed goes, to give you an idea, on [a two CPU
machine], we run 30 developers ... As to [a sixteen CPU
machine], well we haven't been able to find its limits yet!
5. Seems to. Our 14-processor system regularly runs 90 users doing
database inquiries and data entry.
6. My tests say YES!
Q) Given a free choice, would you buy another one...
1. Definitely, yes. I just wish we had the money to do so
2. PUCC (where I worked) ... now has three Symmetries. ... They
have been approached by Convex, Encore, etc.; but the Sequents
evaluate way ahead every time. They plan to buy more, and to
phase out DEC hardware in the process.
3. I don't have one. ...
4. I'd buy three of four more ... I'm sold on sequents ...
5. Yes, and again yes. (We now have three of them, with 8, 14, and
20 processors respectively).
6. Absolutely!
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