Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!ut-emx!reeder
From: reeder@ut-emx.UUCP (William P. Reeder)
Newsgroups: comp.sys.encore
Subject: Re: Umax4.2 R3.3.0 bugs
Summary: welcome to the club, you are member #2
Message-ID: <13276@ut-emx.UUCP>
Date: 22 May 89 23:06:53 GMT
References: <8905181054.AA18446@uunet.UU.NET>
Organization: University of Texas Computation Center
Lines: 43

In article <8905181054.AA18446@uunet.UU.NET>, mlr@goanna.oz.AU (Mark Ross) writes:
> After the machine has been running for a few hours it begins to kill
> new processes. It is at about the same time that the paging activity
> on the system gets very high. The system has about 30 users on it
> and the load is mostly less than 2. Most users just access email
> so the work performed by the system is quite trivial.
> 
> At the time when the paging activity is high the system kills new processes
> and reports
> 	1) No more processes
> 	2) Out of memory
> 
> The system is unusable when it is in this state. The only solution
> is a reboot. The configuration of the 310 system is 1APC,1EMC,16Mbytes and
> 2 Wren IV drives.

Try adding more memory.  We had exactly this problem with a Multimax 320.
Encore claimed that we were underconfigured on memory, they now recommend
16MB per APC card (although that is what you have :-).  Adding more
memory to our system avoided the problem.

If you will look, you will probably find that the system is actually
taking up close to half of the available physical memory, and is simply
refusing to take up any more.  (It dynamically allocates its tables.)
There is probably virtual memory available, the limit being exceeded is
the memory limit for the OS.  The system does start paging madly, since
there are lot's of processes trying to use not much memory, and UMAX
4.2's memory paging/swapping algorithm is not as good as it could be.
Do you see any suspended jobs taking up physical memory?  Or have any
runable jobs completely swapped out?  We did!  Of course, our head
kernel haquer was also scatching his head wondering why the OS was
taking up 15+ megabytes of memory.  So there seems to be two problems:
why is the OS so bloated? and the VM system is not smart enough.

Anyway, adding more memory should help.  Maybe Encore will fix this
problem in UMAX 4.3.

-- Wills
reeder@emx.utexas.edu, uunet!cs.utexas.edu!ut-emx!reeder
-- 
DISCLAIMER:     Opinions expressed above are those of the author and do
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