Xenix Configuration and Configuration Limits

[Peter Jeremy]

In article <3749 at rpp386.UUCP> jfh at rpp386.UUCP (The Beach Bum) writes:
>In article <200 at stca77.stc.oz> peter%stca77 at stcns3.stc.oz (Peter Jeremy) writes:
>>
>>Is Xenix Configuration documented anywhere?  Can anyone give me references
>>to some books?

Maybe I should have said that I have studied the manual entries for CONFIG(C)
and CONFIGURE(C).  I would like more detailed information and _explanations_
of what the various parameters do.

>>Can anyone give me a reasonable explanation of what all the IPC
>>configuration options do?
>>MSGMNI and MSGTQL seem self-explanatory and seem to behave the way I
>>would expect from their brief descriptions.  My attempts to change the
>>other configuration values have generally not had the effect I expected.

>>I am runing SCO Xenix Release 2.2.1 on a 286.  Does anyone know of any ways
>>to increase the following parameters:
>>1) maximum number of open files (NFILE) (currently 400)
>>2) number of message queues (MSGMNI) (currently 40)
>>3) number of message headers (MSGTQL) (currently 100)
>>4) total number of bytes in message queues (currently 8192, but I don't
>>   know why)

>the configuration is quite simple for 2.2.1 and is sort of menu driven.
>you need to run the 'configure' program in /usr/sys.  that should ask you
>all of the questions.  then run link_xenix or something like that and
>reboot.

This I know.  I have used it a fair amount, and it is _much_ nicer than the
procedure for altering the configuration on 2.1.  Only problem is that the
parameters only have a one line "description", which in some cases requires
more knowledge of how the kernel works than I have to adjust sensibly.

>as for the limits you have, are they too small???  my ghod, my 48 user
>68020 machine only has 300 file table entries.  what do you expect???
>this is the configuration info for rpp386, as told by the soon-to-be-posted
>crash program:
> [ configuration info deleted ]
>for two to eight users these numbers should be just fine.  perhaps you
>could enlighten us on how many users you have?

Well, it depends how you count them.  Physically, about five, but through
the wonders of multiscreens and some users having more than 1 terminal,
there are generally 10-15 logins (19 enabled tty's).

The main reason for the high system load is the system we are developing. 
It currently comprises 23 processes, which communicate mostly through
message queues.  Many of the programs also access a database comprising
about 36 files.  In the short term, the system will grow to ~40 processes. 
This leads to a need for a large number of message queues, large message
queue size and lots of open files.  I have recently done some "tuning" of
the database accesing and reduced the number of files needed, my main
limitations are now message queues (and possibly shared memory attaches). 

I have also noticed that the limits quoted by configure are not necessarily
correct in combinations - I have produced kernels that, despite all
configuration parameters being within limits, linking without error and
having data segments <64K, produce nonsense when you start putting a load
on them.
-- 
Peter Jeremy (VK2PJ)         peter%stca77 at stcns3.stc.oz
Alcatel-STC Australia        ...!munnari!stcns3.stc.oz!stca77!peter
41 Mandible St               peter%stca77 at stcns3.stc.oz@uunet.UU.NET
ALEXANDRIA  NSW  2015