386/ix User-level Performance??

John DeArmond john at stiatl.UUCP
Sat Sep 2 07:34:28 AEST 1989

dar at telesoft.telesoft.com (David Reisner) writes:

>I'm considering the purchase of a 386 system to run 386/ix.  So far, I've
>been unable to see one running anywhere, and I'm a bit concerned about
>performance.  As far as user feel is concerned, how does 386/ix on a
>20MHz (or 25MHz?) 386 compare to, say, a Sun 3?  I'm particularly curious
>about the feel of X (or Sunview).  Are the systems similarly responsive?
>Is either system responsive enough for a serious software developer
>actually using Unix?

>I'm sure some of you use both systems, and I'd very much like to hear your
>evaluation.  Thanks.

We use Interactive 386/IX on an AT&T 6386 and on a wyse 386 (sh*tty machine,
but that's another story), Sun 386I's, and a Convergent 630 MightyFrame
which is a 68020 purpose-built unix box running their port of SYS V/R2.

In general, I can say that the Convergent is the fastest I/O-wise, the Suns
are the fastest in the display arena and the Interactive systems both
run a close second.  I am extremely impressed with the speed of interactive's
file system considering that it is working through an AT bus and in one case,
the machine is a 16mhz unit.  A 33mhz PC would probably blow both the Suns
and the Convergent away speed-wise.

Support from Convergent is poor at best.  Sun cannot be beat for support.
It is nice to have hardware and OS support from the same vendor.
As an ISV, we do get support from Interactive.  The things we've called
about to date have been things that should not be issues.

I have been very disappointed at the quality of the ISC release (2.0.1).
The install script would not work from drive B: - ISC tech support 
admitted they'd never tested it from b:.  The asy and uucp is mortally
wounded.  I wrote a replacement uugetty to replace the one supplied so
I could trap out the spurrious signals being generated from somewhere. 
Handling of carrier detect is poor at best and just plain broken at worst.
In one case, when we tried to read from /dev/tty01 directly, an ioctl call 
to put the port in raw mode resulted in the program being dumped back to the 
shell.  No core dump, no warning messages, just a prompt.  I have heard from a 
friend that there is a special way of opening a port and dup()ing the file 
handle that works around this problem but that's not too hot.
Recently, I've replaced the asy drivers with the public domain ones
mentioned in this group.  This seems to fix most problems but it is 
really a poor solution for a high priced OS.

The backup script was broken - I forget the problem, someone else here fixed 
that one.  The sysadmin scripts are close but no cigar.  One must still do 
administration manually because not all necessary functions are included.  

The configuration facility and kernal rebuild is difficult to work with
mainly because of rather poor documentation.  We had to manually edit a
configuration file to turn on a second asy port.  We had an apparent 
interrupt conflict when we added a tape drive - fixed with more manual
editing.  And of course, the problem previously mentioned with
using disks with >1024 cylinders.  We started out with an Adaptec ESDI
controller and switched to the Adeptec 1542A SCSI controller after many
hours of wasted time.  Here, tech support broke down with ISC pointing
a finger at Adaptec and vise versa.  The intelligent controller and
a large, smart SCSI drive is incredible.  Their fast file system really
does work.

An alarmingly few number of devices are supported and those that are
generally are not common or popular units.  It is especially annoying
to find very revision-specific requirements on SCSI devices like
tape drives.  I thought that a degree of hardware independence was a SCSI
goal.  My impression is that the drivers were just sorta hacked together
so as to be able to list many supported devices.  

The VP/IX and X-windows do work, albeit with similiar gotchas caused 
mainly by poor documentation.  And we've found that for serious X applications,
VGA-level resolution is really not enough.

My biggest complaint, after the obvious bugs mentioned above, is about
the documentation.  Aside from being somewhat poorly written, it consists
of perfect-bound paperback books.  You know, the kind that will never lie
flat on a desk and shed pages after some use.  I generally take these
books to the print shop and have holes drilled and the binding sheared off.
And the ones I use the most, I run through a magnifying copier and blow the
pages up to 8.5 X 11".  My greatest plea to Interactive is to give us
decent, usuable documentation.  I'd love to see it all come in 8.5X11"
spiral bound books or something similiar.

My conclusion is that if you are going to ship a product you must support,
go with Sun.  It really is not feasible in a commercial development shop
to be wasting developers' hours fixing what should have been caught in
alpha-testing.  It is very difficult to sell a Unix solution to customers
and/or upper management who are used to the reliability of VMS/DEC, with
these kinds of problems.

If you are strapped for bux and must build a system cheaply,
then Interactive is not a bad choice.  You can build a minimal system 
that will still perform well very cheaply if you shop around a bit.

I do think Interactive needs to look at its pricing structure.  It 
really makes me mad to see Unix unbundled in the first place. (This is
NOT about the 1-2 user vs. unlimited issue.)  But then to see a complete Unix 
system cost more than the hardware it runs on is a bit much. (It has been 
entertaining to see how many netlanders are so ignorant of economics.)  I 
REALLY hate to see Unix being sold so poorly packaged and so overpriced 
because it leaves such a gaping hole for imitation operating systems as OS/2 
to gain a foothold.  I wake up nights sweating at the nightmare of having to 
support an OS/2 platform :-)

This is kinda an ad-hoc list of thoughts.  I'm planning to make a detailed
post of all my problems and workarounds where they exist.  But this list 
should do for now.


John De Armond, WD4OQC                     | Manual? ... What manual ?!? 
Sales Technologies, Inc.    Atlanta, GA    | This is Unix, My son, You 
...!gatech!stiatl!john    **I am the NRA** | just GOTTA Know!!! 

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