From mboxrd@z Thu Jan 1 00:00:00 1970 In-reply-to: <1191516427.5574.7.camel@lappy> (message from Peter Zijlstra on Thu, 04 Oct 2007 18:47:07 +0200) Subject: Re: [PATCH] remove throttle_vm_writeout() References: <1191501626.22357.14.camel@twins> <1191504186.22357.20.camel@twins> <1191516427.5574.7.camel@lappy> Message-Id: From: Miklos Szeredi Date: Thu, 04 Oct 2007 23:07:11 +0200 Sender: owner-linux-mm@kvack.org Return-Path: To: a.p.zijlstra@chello.nl Cc: miklos@szeredi.hu, akpm@linux-foundation.org, wfg@mail.ustc.edu.cn, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: > Yeah, I'm guestimating O on a per device basis, but I agree that the > current ratio limiting is quite crude. I'm not at all sorry to see > throttle_vm_writeback() go, I just wanted to make a point that what it > does is not quite without merrit - we agree that it can be done better > differently. Yes. So what is it to be? Is limiting by device queues enough? Or do we need some global limit? If so, the cleanest way I see is to separately account and limit swap-writeback pages, so the global counters don't interfere with the limiting. This shouldn't be hard to do, as we have the per-bdi writeback counting infrastructure already, and also a pseudo bdi for swap in swapper_space.backing_dev_info. Miklos -- 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/ . Don't email: email@kvack.org