Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!unmvax!pprg.unm.edu!topgun.dspo.gov!lanl!cmcl2!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.sys.apple
Subject: Re: PURGE-O-MATIC AND DPII
Message-ID: <10837@smoke.BRL.MIL>
Date: 28 Aug 89 06:05:35 GMT
References: <689@mountn.dec.com>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 11

In article <689@mountn.dec.com> shatara@memit.dec.com (Chris Shatara) writes:
>Worked like a champ!  Now what I would like to know is what exactly does
>purge-o-matic actually do?  Why is it needed or what is it about DPII that 
>makes this necessary.

Zink or somebody also published a Paintworks Gold patch for similar purposes.
It appears to me that these applications insist on glomming onto a large
contiguous storage array, and give up if they don't get it.  Purging the
dynamically-allocated memory ensures that they'll get it, if it's available.
The PWG patch (I think) makes PWG no longer limit its request to the lowest
1.25MB, but allows free memory from other locations to be used if necessary.