From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 6 Jun 2001 21:06:52 +0200 (CEST) From: Mike Galbraith Subject: Re: Break 2.4 VM in five easy steps In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: "Eric W. Biederman" Cc: Derek Glidden , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On 6 Jun 2001, Eric W. Biederman wrote: > Derek Glidden writes: > > > > The problem I reported is not that 2.4 uses huge amounts of swap but > > that trying to recover that swap off of disk under 2.4 can leave the > > machine in an entirely unresponsive state, while 2.2 handles identical > > situations gracefully. > > > > The interesting thing from other reports is that it appears to be kswapd > using up CPU resources. Not the swapout code at all. So it appears > to be a fundamental VM issue. And calling swapoff is just a good way > to trigger it. > > If you could confirm this by calling swapoff sometime other than at > reboot time. That might help. Say by running top on the console. The thing goes comatose here too. SCHED_RR vmstat doesn't run, console switch is nogo... After running his memory hog, swapoff took 18 seconds. I hacked a bleeder valve for dead swap pages, and it dropped to 4 seconds.. still utterly comatose for those 4 seconds though. -Mike -- 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/