Gentoo Archives: gentoo-performance

From: Florian Koenig <k0255220@××××××××××××××××××××.at>
To: gentoo-performance@l.g.o
Subject: RE: [gentoo-performance] swap?
Date: Fri, 30 Jul 2004 19:22:24
Message-Id: PHEAKLEGNEFNJGPCIHANCEEHCKAA.k0255220@students.uni-linz.ac.at
In Reply to: Re: [gentoo-performance] swap? by Colin Kingsley
> > Also, when I do > > > > free > > > > it shows no swap is used even though physical memory level is 98%. > > free shows no swap used on my system either. and 90% or more physical > memory use is standard for the linux kernel.
Exactly. In contrast to Windows NT/2000/XP, which tries to swap out as much pages as possible, Linux tries to keep the memory mostly filled. Lots of the memory gets used as cache and buffer so you might actually gain some performance. The difference between Windows and Linux stems from their different origins. Linux/Unix was always meant to be a server system where the set of running processes doesn't change that often. Therefore it tries to keep pages in memory for as long as possible. Windows' approach to the problem is geared to desktop performance and so it swaps out 'unused' pages as soon as possible to free memory and keep startup time short for programs being loaded. The behaviour of Linux is actually hotly debated by the developers as you can see on these two pages, which btw also include some hints on how to tune swapping: http://kerneltrap.org/node/view/3000 http://kerneltrap.org/node/view/3202 Have a nice weekend and kind regards floki -- gentoo-performance@g.o mailing list

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Subject Author
Re: [gentoo-performance] swap? "Douglas Breault Jr." <GenKreton@×××××××.net>