From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH/RFC 0/14] Page Reclaim Scalability From: Peter Zijlstra In-Reply-To: <20070914205359.6536.98017.sendpatchset@localhost> References: <20070914205359.6536.98017.sendpatchset@localhost> Content-Type: text/plain Date: Fri, 14 Sep 2007 23:11:03 +0200 Message-Id: <1189804264.5826.5.camel@lappy> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Lee Schermerhorn Cc: linux-mm@kvack.org, akpm@linux-foundation.org, mel@csn.ul.ie, clameter@sgi.com, riel@redhat.com, balbir@linux.vnet.ibm.com, andrea@suse.de, eric.whitney@hp.com, npiggin@suse.de, Linus Torvalds List-ID: On Fri, 2007-09-14 at 16:53 -0400, Lee Schermerhorn wrote: > 1) make-anon_vma-lock-rw > 2) make-i_mmap_lock-rw > > The first two patches are not part of the noreclaim infrastructure. > Rather, these patches improve parallelism in shrink_page_list()-- > specifically in page_referenced() and try_to_unmap()--by making the > anon_vma lock and the i_mmap_lock reader/writer spinlocks. Also at Cambridge, Linus said that rw-spinlocks are usually a mistake. Their spinning nature can cause a lot of cacheline bouncing. If it turns out these locks still benefit, it might make sense to just turn them into sleeping locks. That said, even sleeping rw locks have issues on large boxen, but they sure give a little more breathing room than mutal exclusive locks. -- 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