From owner-freebsd-questions Mon Oct 28 14:04:01 1996 Return-Path: owner-questions Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id OAA06757 for questions-outgoing; Mon, 28 Oct 1996 14:04:01 -0800 (PST) Received: from nora.pcug.co.uk (Nora.PCUG.CO.UK [192.68.174.71]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id OAA06730 for ; Mon, 28 Oct 1996 14:03:55 -0800 (PST) Received: from imdb.demon.co.uk by nora.pcug.co.uk id aa22814; 28 Oct 96 22:03 GMT Message-Id: <199610282201.WAA10772> Subject: Re: server death when swap space is all gone. To: freebsd-questions@freebsd.org Date: Mon, 28 Oct 1996 22:01:46 +0000 (GMT) From: Rob Hartill Organization: Internet Movie Database Reply-To: robh@imdb.com X-pgp-public-key: http://us.imdb.com/pgp.html X-Mailer: ELM [version 2.4 PL24 ME8a] Content-Type: text Sender: owner-questions@freebsd.org X-Loop: FreeBSD.org Precedence: bulk John Dyson wrote: > >(The "humor" in this message is not directed to the original poster, but > perhaps is slightly misguided Linux oriented friend :-)). > >> >> On a related note, a Linux using friend takes pleasure in telling me >> that FreeBSD is brian-dead w.r.t memory management because it can't diff >> a couple of 20Mb files on a machine with ample memory and swap (combined). >> >Didn't know that diff used mmap? Linux is brain-dead because it doesn't >push unused pages out to swapspace, until memory needs to be freed. :-). >You know that it is faster to free up the memory, thereby letting the >system utilize the ram, as opposed to tying it up with stuff that should >be on swap? :-). Many of the complaints are due to people not >understanding this bit of info (or perhaps Linux fervor)... I know linux is crap, but the simple fact is my 96Mb FreeBSD machine with 77Mb of swap, doing nothing but "diff" on two files falls over with "diff: memory exhausted", while a 48mb linux machine with ? swap can produce the 700k diff file. When I run diff, "top" shows no evidence that the swap is being used or that 'cache' memory being reclaimed. The process grows to 33Mb then reports "diff: memory exhausted". I think we tried this once on a FreeBSD machine with far more swap and it failed there too. Why does the FreeBSD's superior memory management let me down ? -- Rob Hartill (robh@imdb.com) http://www.imdb.com/ ... why wait for a clear night to see the stars?.