From owner-freebsd-stable Sun Apr 5 14:28:37 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id OAA16806 for freebsd-stable-outgoing; Sun, 5 Apr 1998 14:28:37 -0700 (PDT) (envelope-from owner-freebsd-stable@FreeBSD.ORG) Received: from mail.kersur.net (root@mail.kersur.net [199.79.199.3]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id OAA16273; Sun, 5 Apr 1998 14:27:10 -0700 (PDT) (envelope-from dswartz@druber.com) Received: from manticore (manticore.druber.com [207.180.95.108]) by mail.kersur.net (8.8.8/8.8.8) with SMTP id RAA11866; Sun, 5 Apr 1998 17:27:43 -0400 (EDT) Message-Id: <3.0.5.32.19980405172640.00915e30@mail.kersur.net> X-Sender: druber@mail.kersur.net X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.5 (32) Date: Sun, 05 Apr 1998 17:26:40 -0400 To: dg@root.com From: Dan Swartzendruber Subject: Re: swap-leak in 2.2.5 ? Cc: dag-erli@ifi.uio.no (Dag-Erling Coidan =?iso-8859-1?Q?Sm=F8rgrav?= ), stable@FreeBSD.ORG, current@FreeBSD.ORG In-Reply-To: <199804052022.NAA11264@implode.root.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk At 01:22 PM 4/5/98 -0700, David Greenman wrote: >>while. It's simply a *lot* faster to keep already-linked executables >>in memory (and move them into swap when memory goes full) rather than >>throwing them out and having to reload and relink them next time they >>are invoked, as long as they haven't changed in the meantime. >> >>David, I hope my explanation is not too far off? > > Actually, it's not that the system has to do any re-linking. The reason >that swap space is consumed even when you have plenty of memory is that the >system also tries to cache regular file data, so freeing up memory for that >by moving modified but not recently used process pages to swap is usually a >good thing. My only quibble with this technique is that it would seem to make it harder to tell if your machine is really running low on swap or not (e.g. swap as backing store for stack/heap/whatever *is* critical and allocation failure can cause application failure, whereas swap being used to cache random cruft is in the "who really cares" department). Or is there some way to tell the difference? To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message