From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 12 Jul 2007 10:18:57 +0200 From: Nick Piggin Subject: Re: [patch] mm: unlockless reclaim Message-ID: <20070712081857.GC1830@wotan.suse.de> References: <20070712041115.GH32414@wotan.suse.de> <20070712004339.0f5b7a2f.akpm@linux-foundation.org> <20070712075532.GB1830@wotan.suse.de> <20070712010007.164acc8e.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070712010007.164acc8e.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Linux Memory Management List List-ID: On Thu, Jul 12, 2007 at 01:00:07AM -0700, Andrew Morton wrote: > On Thu, 12 Jul 2007 09:55:32 +0200 Nick Piggin wrote: > > > > > > > mutter. > > > > > > So why does __pagevec_release_nonlru() check the page refcount? > > > > It doesn't > > yes it does That was in answer to your question: I mean: it doesn't need to. > > although it will have to return the count to zero of course. > > > > I don't want to submit that because the lockless pagecache always needs > > the refcount to be checked :) And which I am actually going to submit to > > you after you chuck out a few patches. > > > > But unlock_page is really murderous on my powerpc (with all the > > unlock-speeup patches, dd if=/dev/zero of=/dev/null of a huge sparse file > > goes up by 10% throughput on the G5!!). > > well this change won't help that much. Oh, well the dd includes reclaim and so it ends up doing 2 locks for each page (1 to reading, 1 to reclaim). So this alone supposedly should help by 5% :) -- 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