From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 27 Mar 2000 17:17:39 +0100 From: "Stephen C. Tweedie" Subject: Re: compressed swap Message-ID: <20000327171739.F10820@redhat.com> References: <38DF5901.CEBF90B0@nibiru.pauls.erfurt.thur.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <38DF5901.CEBF90B0@nibiru.pauls.erfurt.thur.de>; from weigelt@nibiru.pauls.erfurt.thur.de on Mon, Mar 27, 2000 at 12:50:09PM +0000 Sender: owner-linux-mm@kvack.org Return-Path: To: Enrico Weigelt Cc: "linux-mm@kvack.org" , Stephen Tweedie List-ID: Hi, On Mon, Mar 27, 2000 at 12:50:09PM +0000, Enrico Weigelt wrote: > > i'm currenty thinking about a compressed swapspace-manager. > not to save diskspace, but to reduce the IO-upcome. > > in today's PCs the blottleneck is the disk-bandwith when the > system is swapping.i Not really. You are far more limited by the seek performance of the disk than by its bandwidth. If you wanted to optimise it, you would be far, far better off trying to make swap stream on and off the disk in larger units rather than compressing it. (The clustering code in the 2.2 VM does this for swapin, and the kswapd is tuned to do it for swapout, to some extent already.) --Stephen -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/