From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx187.postini.com [74.125.245.187]) by kanga.kvack.org (Postfix) with SMTP id 9583C6B0037 for ; Wed, 5 Jun 2013 19:07:40 -0400 (EDT) Date: Wed, 5 Jun 2013 16:07:38 -0700 From: Andrew Morton Subject: Re: [PATCH v10 04/35] dentry: move to per-sb LRU locks Message-Id: <20130605160738.fe46654369044b6d94eadd1b@linux-foundation.org> In-Reply-To: <1370287804-3481-5-git-send-email-glommer@openvz.org> References: <1370287804-3481-1-git-send-email-glommer@openvz.org> <1370287804-3481-5-git-send-email-glommer@openvz.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: linux-fsdevel@vger.kernel.org, Mel Gorman , Dave Chinner , linux-mm@kvack.org, cgroups@vger.kernel.org, kamezawa.hiroyu@jp.fujitsu.com, Michal Hocko , Johannes Weiner , hughd@google.com, Greg Thelen , Dave Chinner On Mon, 3 Jun 2013 23:29:33 +0400 Glauber Costa wrote: > From: Dave Chinner > > With the dentry LRUs being per-sb structures, there is no real need > for a global dentry_lru_lock. The locking can be made more > fine-grained by moving to a per-sb LRU lock, isolating the LRU > operations of different filesytsems completely from each other. What's the point to this patch? Is it to enable some additional development, or is it a standalone performance tweak? If the latter then the patch obviously makes this dentry code bloatier and straight-line slower. So we're assuming that the multiprocessor contention-avoidance benefits will outweigh that cost. Got any proof of this? -- 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