From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: Please test: workaround to help swapoff behaviour Message-ID: From: "Bulent Abali" Date: Fri, 8 Jun 2001 19:53:35 -0400 MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org Return-Path: To: Marcelo Tosatti Cc: Mike Galbraith , "Eric W. Biederman" , Derek Glidden , lkml , linux-mm@kvack.org List-ID: >> I looked at try_to_unuse in swapfile.c. I believe that the algorithm is >> broken. >> For each and every swap entry it is walking the entire process list >> (for_each_task(p)). It is also grabbing a whole bunch of locks >> for each swap entry. It might be worthwhile processing swap entries in >> batches instead of one entry at a time. >> >> In any case, I think having this patch is worthwhile as a quick and dirty >> remedy. > >Bulent, > >Could you please check if 2.4.6-pre2+the schedule patch has better >swapoff behaviour for you? No problem. I will check it tomorrow. I don't think it can be any worse than it is now. The patch looks correct in principle. I believe it should go in to 2.4.6. But I will test it. On small machines people don't notice it, but otherwise if you have few GB of memory it really hurts. Shutdowns take forever since swapoff takes forever. -- 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-mm.org/