From owner-freebsd-security Wed Aug 11 11:52:17 1999 Delivered-To: freebsd-security@freebsd.org Received: from orion.ac.hmc.edu (Orion.AC.HMC.Edu [134.173.32.20]) by hub.freebsd.org (Postfix) with ESMTP id 7E801155A8 for ; Wed, 11 Aug 1999 11:52:05 -0700 (PDT) (envelope-from brooks@one-eyed-alien.net) Received: from localhost (brdavis@localhost) by orion.ac.hmc.edu (8.8.8/8.8.8) with ESMTP id LAA14101; Wed, 11 Aug 1999 11:51:11 -0700 (PDT) From: brooks@one-eyed-alien.net X-Authentication-Warning: orion.ac.hmc.edu: brdavis owned process doing -bs Date: Wed, 11 Aug 1999 11:51:11 -0700 (PDT) X-Sender: brdavis@orion.ac.hmc.edu To: David Gilbert Cc: "'freebsd-security@FreeBSD.ORG '" Subject: Re: 4 Swap partitions limit (was Re: RE: Little question (offtopic)) In-Reply-To: <14257.50009.162402.381699@trooper.velocet.ca> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Wed, 11 Aug 1999, David Gilbert wrote: > One curious aspect of FreeBSD that I havn't explained to my own > satisfaction is why it appears to consume more swap than linux. I see > a lot of linux installations running on 32 or 64M of swap, but I'm > loathe to set up BSD boxes with less than 256M of swap. > > Not that I have scientific evidence of this, but it has been a general > feeling of a number of people I know. Lots of people get this feeling, which is why it's a FAQ :-): --cut-- 12.1: FreeBSD uses far more swap space than Linux. Why? FreeBSD only appears to use more swap than Linux. In actual fact, it does not. The main difference between FreeBSD and Linux in this regard is that FreeBSD will proactively move entirely idle, unused pages of main memory into swap in order to make more main memory available for active use. Linux tends to only move pages to swap as a last resort. The perceived heavier use of swap is balanced by the more efficient use of main memory. Note that while FreeBSD is proactive in this regard, it does not arbitrarily decide to swap pages when the system is truely idle. Thus you will not find your system all paged out when you get up in the morning after leaving it idle overnight. --cut-- -- Brooks P.S. trimmed the CC list since this wasn't very on-topic. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message