From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from atlas.CARNet.hr (zcalusic@atlas.CARNet.hr [161.53.123.163]) by kvack.org (8.8.7/8.8.7) with ESMTP id DAA03853 for ; Thu, 3 Dec 1998 03:55:33 -0500 Subject: Re: [PATCH] swapin readahead References: <87vhjvkccu.fsf@atlas.CARNet.hr> <199812021735.RAA04489@dax.scot.redhat.com> <87d862gs3h.fsf@atlas.CARNet.hr> Reply-To: Zlatko.Calusic@CARNet.hr Mime-Version: 1.0 From: Zlatko Calusic Date: 03 Dec 1998 09:55:13 +0100 In-Reply-To: ebiederm+eric@ccr.net's message of "02 Dec 1998 23:25:38 -0600" Message-ID: <8767bt7gge.fsf@atlas.CARNet.hr> Sender: owner-linux-mm@kvack.org To: "Eric W. Biederman" Cc: "Stephen C. Tweedie" , Rik van Riel , Linux MM List-ID: ebiederm+eric@ccr.net (Eric W. Biederman) writes: > >>>>> "ZC" == Zlatko Calusic writes: > > ZC> Trying 2.1.131-2, I'm mostly satisfied with MM workout, but... > > ZC> Still, I have a feeling that limit imposed on cache growth is now too > ZC> hard, unlike kernels from the 2.1.1[01]? era, that had opposite > ZC> problems (excessive cache growth during voluminous I/O operations). > > My gut reaction is that we need a check in swap_out to see if we have > written out a swap_cluster or some other indication that we have > started all of the disk i/o that is reasonable for now and need to > switch to something else. I tried that approach (Rik has tried also) but only to find that swapout speed drops. Will investigate further... > > This should have the same effect as the switches with the limits on > the swap cache but more autobalancing. I'm nervous of a kernel that > needs small limits on it's disk cache to work correctly. Yes, that is exactly my point. I'm glad there is at least one person to share an opinion with. :) > > ZC> What I wanted to ask is: do you guys share my opinion, and what > ZC> changes would you like to see before 2.2 comes out? > > One thing worth putting in. Probably before to 2.2 but definentily > before any swap page readahead is done is to start using brw_page > for swapfiles. I don't know about synchronous cases, but in the when > asynchronous operation is important it improves swapfile performance > immensely. > Speaking about swap files (as opposed to swap partitions) what is the reason for synchronous operation when swapping to them, at first place? Races? -- Posted by Zlatko Calusic E-mail: --------------------------------------------------------------------- If you can't make it good, make it LOOK good." B. Gates -- This is a majordomo managed list. To unsubscribe, send a message with the body 'unsubscribe linux-mm me@address' to: majordomo@kvack.org