From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wu Fengguang Subject: Re: [PATCH 5/8] readahead: add /debug/readahead/stats Date: Tue, 22 Nov 2011 22:14:20 +0800 Message-ID: <20111122141420.GA29261@localhost> References: <20111121091819.394895091@intel.com> <20111121093846.636765408@intel.com> <20111121141759.GE24062@one.firstfloor.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andrew Morton , Linux Memory Management List , "linux-fsdevel@vger.kernel.org" , Ingo Molnar , Jens Axboe , Peter Zijlstra , Rik van Riel , LKML To: Andi Kleen Return-path: Content-Disposition: inline In-Reply-To: <20111121141759.GE24062@one.firstfloor.org> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org Andi, On Mon, Nov 21, 2011 at 10:17:59PM +0800, Andi Kleen wrote: > > +static unsigned long ra_stats[RA_PATTERN_MAX][RA_ACCOUNT_MAX]; > > Why not make it per cpu? That should get the overhead down, probably > even enough that it can be enabled by default. > > BTW I have an older framework to make it really easy to add per > cpu stats counters to debugfs. Will repost, that would simplify > it even more. That's definitely a good facility to have. I would be happy to become its first user :) Thanks, Fengguang -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org