Bell Tech 386 SysVr3

[William E. Davidsen Jr]

In article <1988Jul30.141708.3175 at gpu.utcs.toronto.edu> woods at gpu.utcs.Toronto.EDU (Greg Woods) writes:

| Anyone who thinks Xenix is reliable has NEVER seen a truely reliable system.
| I worked with >10 Xenix 2.2.1 286 systems for a period 9 months.  At
| least one of them crashed every (working) day, and often they were up and
| down like yo-yo's.  Many of the crashes were due to kernel bugs.  Only a
| small percentage could be attributed to hardware or local software (ie.
| device drivers).  Many of the bugs are still un-found.

  Must depend on how you use it. I've been running Xenix for 3 years on
a 286 and 1+ years on a 386, and have had exactly one kernel crash. My
work system is handling several uucp connections, telnet and ftp access,
mail reading etc. The home system is public access UNIX, and people try
to crash it all the time.

| I've only managed to crash 386/ix once.  There's a (known) bug with shl.

| The Xenix serial driver cannot share interrupt vectors with more than
| one port.  It will lose data at 1200 baud.

  I run one 2400 baud and one 9600 baud connection at the same time as
ftp, and have not seen this. I've heard of problems when someone tries
to same $$ and use a dumb serial card for multiple ports. Perhaps that
what you meant.

| Interrupt driven ports ALWAYS take a lot of cpu.  Try a really smart
| board, such as Consensys PowerPorts.

  Amen!

| The real problem is that SCO have built up a tremendous support
| reputation, and they are very wary of making any changes that may have
| dozens of users calling up.

  I agree, no one ever accused MicroPort of having a great support
reputation, and if INteractive gives the same support they did four
years ago, they don't have to worry either. First time I ever heard a
good reputation used as a drawback.

| dozens of users calling up.  Take for example the choice to make the
| user utilities display disk blocks as 512 byte units, even though the
| 2.x kernel uses 1024 byte blocks.  One support person hinted to me that
| they did not want to scare people who did a df, and found half their
| disk was suddenly gone!

  That is certainly the case with a number of companies. I could even
make a case for doing it that way if I had dozens of shell scripts which
expect a certain format for the file sizes and free space, etc,
including using the find command with size option. 

  I think you're correct in thinking that because Xenix has an installed
base SCO doesn't have the freedom to change things, but then having an
installed base is a good thing in general, isn't it?

| >compile from 386 to Xenix/286, 8086 and DOS. Xenix has a lot of

| This can be a very valuable selling point, but 386's (with VP/ix or
| Merge) make it moot.

  Only if the cost of buying separate software for DOS doesn't count. By
the time you buy a C compiler, editor, assembler, and some other tools
you may have spent what looks like 10-20% of the cost of the hardware.
Plus DOSmerge. Don't misunderstand, I have vp/ix and use it, but only to
test software, not to try and duplicate my UNIX tools in DOS.

| >tested, generating code which crashed the assembler a suite which runs
| >on BSD, Ultrix, Xenix, SunOS, SVR3 on 3B2/200, etc.
| 
| I don't want to be offensive, but are you sure you know what you are
| doing?  Most code that is that portable will compile first time.  At
| least it does for me.  Did you do the obvious things, like fix up the
| makefile, and any configure/tuning headers, etc.?

  Actually the first program which crashed it is about ten lines (plus
comments) and doesn't have a make file, header file, etc. The second
failure caused the compiler to core dump, and another to make the
assembler reject the output of the compiler "error: there is no register
25" as I recall, definitely trying to find a register not in the 80386.
There were others, mainly causing core dumps. I can accept a compiler
which claims to find errors where no compiler has before, but I don't
think generating bad code or core dumps is a useful behavior.
-- 
	bill davidsen		(wedu at ge-crd.arpa)
  {uunet | philabs | seismo}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me