From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 12 Jul 2000 02:52:26 +0200 (CEST) From: Andrea Arcangeli Subject: Re: [PATCH] 2.2.17pre7 VM enhancement Re: I/O performance on 2.4.0-test2 In-Reply-To: <396bb43f.25232236@mail.mbay.net> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: John Alvord Cc: "Juan J. Quintela" , Rik van Riel , "Stephen C. Tweedie" , Marcelo Tosatti , Jens Axboe , Alan Cox , Derek Martin , Linux Kernel , linux-mm@kvack.org, "David S. Miller" List-ID: On Wed, 12 Jul 2000, John Alvord wrote: >One question that puzzles me... cache for disk files and cache for >program data will have very unlike characteristics. Executable program Agreed. That is exactly what I'm trying say by telling that lru_cache and lru_mapped_cache have different implicit priorities and we can't threat them in the same way. >enough, what algorithm is used to achieve an effective balance of >usage? In 2.[234].x we basically first try to shrink the cache for disk and when we run low in cache for disk (so when we start to fail in shrinking it) we fallback shrinking the cache for program. That's sane algorithm even if currently it's not very smart in understanding when it's time to shrink the cache for programs and it's also not able to shrink it properly in some case. Andrea -- 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/