SunOS 4.* seems much slower

[David Gast]

In article <494 at brchh104.bnr.ca> gast at cs.ucla.edu (David Gast) writes:
>The problem is that SunOs 4.* (I
>think we are using 4.0.3) seems much slower than SunOs 3.5.

Thanks to all who replied.

Executive Summary:

SunOS 4.0.* is slower than SunOS 3.5.* or 4.1.*.  (* is the shell
meta-character).  It also takes at least 4 Meg more memory than 3.5.  If
you haven't updated from 3.5, don't.  If you have, then update to 4.1.
Many of the respondants suggested that we need at least 8 meg of memory on
a machine; our machines either have 16 or 32 meg of memory.  (Some
workstations do not, but they don't seem to be having serious problems).

Incidentally, after I posted the message, it was determined that the major
cause of our problems seems to be NFS.  Specifically rcp (which uses
tcp/ip) can sometimes copy a file significantly faster than cp (which uses
NFS).  In fact, copying a large file with NFS can slow down an entire
network.  Note: sometimes nfs is faster, perhaps when the system is not
heavily loaded.

Here are the replies I received, edited.

X-From curt at ecn.purdue.edu Wed Nov 28 11:44:57 1990

Yep, bigger is slower.  4.1.1 is supposed to address this problem, and is
supposedly faster than 4.0 or 4.0.3.  I will believe it when I am running
it.  In the meantime, build yourself a non GENERIC kernel, and install as
much memory as you can afford in the server, and clients.  This will help
immensely.

X-From karl at forest.gsfc.nasa.gov Wed Nov 28 14:03:14 1990

How much RAM do you have?  OS4.x is slower on machines with <8MB because
it is quite a bit *larger* than 3.5, and it has to swap a lot if there's
not enough physical memory.

X-From eirik at theory.TN.CORNELL.EDU Wed Nov 28 17:13:58 1990

SunOS 4.1 is supposed to be noticably faster than 4.0.3; my understanding
is that it was the first release after 4.0 which was specifically tuned
for performance.

X-From montjoy at nest.ece.uc.edu Thu Nov 29 06:08:48 1990

4.xx is much slower. However, it has more features than 3.5. Also, these
performance issues are being addressed in 4.1 and 4.1.1.  4.1xxx has
better interactive performance, and faster SCSI disk support.

X-From jdd at ois.db.toronto.edu Thu Nov 29 11:12:16 1990

If mem <  8MB, 3.5 is faster than 4.1, which in turn is faster than 4.0.
If mem >= 8MB, 4.1 is faster than 4.0 which is faster than 3.5.

X-From tacitus!clh at wimsey.bc.ca Thu Nov 29 13:39:54 1990

A lot of 4.0.X is slower than 3.5; a few things (like NFS) are supposed to
be improved.

One of the most important things about 4.0.X is that it REALLY NEEDS more
memory than 3.5; for instance, our 3/60s were unbearable with 4Mb, but are
quite satisfactory at 8 (this running SunView).

4.1 appears to be somewhat of an improvement over 4.0.3; Sun claims 17%
average (average? average what??) improvement.  You still need the memory,
though.

There are all sorts of tuning things in the Installing the SunOS manual,
but many of these appear unnecessary if you have 8Mb.

All this is further messed up by OpenWindows, which seems to require at
least 12Mb to function pleasantly (ie not paging when pulling a window to
the foreground).

One last thing; we run one 3/50 (which is really bad under 4.1), two 8Mb
3/60s (which are OK), and one 12Mb 3/60 (which is also OK); the rest of
our machines are SS1s.  The SS1s, presumably because of the bigger SPARC
binaries, seem to often "fall over" the minimum memory line, ie, if you
have an application that barely runs comfortably on an 8mb 3/60, you'll
need 12mb on your 4/60.

Oh yes, the other thing I remember seeing was a (Sun) comparision that
showed Sun 4s performed better on average with 4.0.X than 3.4, and Sun 3s
slightly worse.

X-From henry at zoo.toronto.edu Thu Nov 29 14:51:25 1990

It *is* much slower.  Which is part of the reason why some of us are still
running 3.5.

X-From dgsi!cimage.com!brian at umich.edu Fri Nov 30 21:26:41 1990

I agree with you.  We run 4.0.3(c), 4.1 and 4.1.1 where I work.  At home,
I run 3.5 on a 3/60.  

Of the 4.X products, it would seem that 4.1.1 is quite a bit better than
the others.  I have not run 4.1.1 on a Sun 3, however.  SunOS 4.X is a
PIG!

I like 3.5.  While it is by no means petite, it is small and quick
compared to Sun's 4.X offerings.  I am somewhat tempted to give 4.1.1 a
try, but I don't like the idea of having to reinstall 3.5 later (my SCSI
disk is a kludge. I think it will work fine under 4.X, but it was a real
bitch under 3.5).

It sounds like some of the delays and slowness that you may be
experiencing may be due to other problems.  4.X does require more memory.
If your config doesn't allow for this (if you're ok with os 3.5 and 4 meg,
then you're probably screwed with 4.X and 4 meg).  For 4.X to be
reasonable, you must have enough memory.  A bummer, but what can I say?  

Seeing how 4.X has grown (and the problems with 4.0), I do NOT look
forward to the merge with SYS V R4... Ugh...

X-From samsung!romed!asuvax.eas.asu.edu!mcdphx!zztop!xroads!lindley at uunet.UU.NET Sun Dec  2 21:59:21 1990

[Swi]tch to 4.1. My users all claim that it is, if anything, a bit faster
than 3.5 was, and they are a really picky bunch. 4.0.3 is known to be LOTS
slower than 4.1 or 3.5!

X-From smcnet!ism!ico!gvlv2.gvl.unisys.com!ico!faatcrl!warb Mon Dec  3 22:39:50 1990

SunOs 3.5 was a bit faster, but you need at least 8mb of ram to run the
4.* systems on. Sounds like you have a 4mb system,which the 3.5 systems
ran ok on.

X-From hyder at erg.sri.com Tue Dec  4 08:00:30 1990

You most likely are in need of more memory.  The single biggest difference
between SunOS 3.5 and 4.N was the change to vm that implements shared
libraries.  The shared libraries are locked into memory leaving less for
running processes and that often leads to thrashing.

Whatever you used to consider a good amount of memory under 3.5 add 4Meg.
It is not worth trying to run SunOS 4.n in less than 8Meg!

David Gast
gast at cs.ucla.edu
{uunet,ucbvax,rutgers}!{ucla-cs,cs.ucla.edu}!gast