From:	CSBVAX::MRGATE!tencati@VLSI.JPL.NASA.GOV@SMTP 19-FEB-1988 02:01
To:	ARISIA::EVERHART
Subj:	Re: Need help on memory related system tuning


Received: from VLSI.JPL.NASA.GOV by KL.SRI.COM with TCP; Mon 15 Feb 88 20:53:03-PST
Date:    Mon, 15 Feb 88 20:53:48 PST
From:     tencati@VLSI.JPL.NASA.GOV (Ron Tencati)
Message-Id: <880215205348.1ead@VLSI.JPL.NASA.GOV>
Subject: Re: Need help on memory related system tuning
To:       info-vax@kl.sri.com
X-ST-Vmsmail-To: ST%"info-vax@kl.sri.com"

  
  Ralph,
  
  In your user's batch files, have them do a SHOW PROCESS/ACCOUNTING before they
  log off (your interactive users can do this too).  Look at the Virtual Page
  Count.  You may be restricting your users to too little physical memory.
  
  The number of peak virtual pages used will be your key.  If your users are 
  hitting their /wsextent value with their "peak physical memory" usage, and
  exceeding it with their "peak virtual usage", then consider upping that 
  user`s /wsquo and /wsextent parameters.  This will reduce the number of
  page faults at the expense of using more physical memory.
  
  A batch job using lots of memory (/wsquo, /wsextent) running at prio 1 will 
  lock up resources longer.  We run a job limit of 2 on our slow batch queue.
  
  Don't alter base priority of 4.  If you feel you need this, there is a program
  called NANNY (available in source from ZAR@Hamlet.Caltech.EDU) that allows for
  automatic/dynamic adjustment of priorities based on system load and job
  requirements.  It's a pretty good program, but it also consumes it's share
  of resources albeit small.
  
  Check your PFRATL sysgen parameter.  If you set it to zero, you disable 
  working set "shrinking", which again at the cost of using more physical
  memory will reduce page faults (this is a dynamic parameter - you can 
  change it to zero, see how the system reacts, then change it back if
  you wish).
  
  You're bound to get more information from the list, but  I think I hit on 
  the major points.
  
  Good Luck,
  
  Ron Tencati
  System Mgr, VLSI.JPL.NASA.GOV