From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 17 Jul 2000 14:02:09 -0300 (BRST) From: Rik van Riel Subject: Re: [PATCH] 2.2.17pre7 VM enhancement Re: I/O performance on In-Reply-To: <397337EF.58667DD@colorfullife.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Manfred Spraul Cc: linux-mm@kvack.org List-ID: On Mon, 17 Jul 2000, Manfred Spraul wrote: > Rik van Riel wrote: > > > > Actually, FreeBSD has a special case in the page fault code > > for sequential accesses and I believe we must have that too. > > Where is that code? It's in vm_fault.c, look for the readaround code. > > Both LRU and LFU break down on linear accesses to an array > > that doesn't fit in memory. In that case you really want > > MRU replacement, with some simple code that "detects the > > window size" you need to keep in memory. This seems to be > > the only way to get any speedup on such programs when you > > increase memory size to something which is still smaller > > than the total program size. > > Do you have an idea how to detect that situation? I've got some ideas, but they need to be polished a bit before I can put them into code. I'll probably do this at OLS... regards, Rik -- "What you're running that piece of shit Gnome?!?!" -- Miguel de Icaza, UKUUG 2000 http://www.conectiva.com/ http://www.surriel.com/ -- 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/