Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!gem.mps.ohio-state.edu!ginosko!uunet!mcsun!ukc!dcl-cs!aber-cs!thor!pcg From: pcg@thor.cs.aber.ac.uk (Piercarlo Grandi) Newsgroups: gnu.emacs Subject: Re: Garbage Collecting (and Memory Usage) Message-ID: Date: 8 Sep 89 15:30:26 GMT References: Sender: pcg@aber-cs.UUCP Organization: Coleg Prifysgol Cymru Lines: 29 In-reply-to: kindred@dopey.telesci.UUCP's message of 6 Sep 89 23:11:05 GMT To: In article kindred@dopey.telesci.UUCP (David L Kindred (Dave)) writes: Having used GNU Emacs for a while, and having had the opportunity to upgrade it from 18.52 to 18.54, and do other various assorted things, I do not recall ever seeing a discussion of Memory Usage versus Garbage Collection Frequency versus Garbage Collection Duration. (If it makes any difference, I'm running Emacs 18.54 on a Sun 3/50 with 4 Meg of RAM. I should have a 8 meg 3/60 or 3/80 by October. I hope that the extra 4 meg will ease some of my problems.) I have a 2 meg 386 at home, and since the discs are on my desk, I can hear the clatter of seeks... It is fairly obvious that in general GNU programs have *very* poor locality of reference; they seem to be built under the assumption of infinite *real* memory, not infinite *virtual* memory. I think that obviating this, at least for Emacs, is not a big problem, for somebody that knows well its structure. Garbage collecting GNU emacs is usually fast enough (CPU wise); what I find really annoying is the heavvy paging rate between garbage collections... What about a nice packing collector? or a copying compatctifying one? Oh, please, please! (plea to RMS for version 19). -- Piercarlo "Peter" Grandi | ARPA: pcg%cs.aber.ac.uk@nsfnet-relay.ac.uk Dept of CS, UCW Aberystwyth | UUCP: ...!mcvax!ukc!aber-cs!pcg Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk