From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755926AbYJWGmt (ORCPT ); Thu, 23 Oct 2008 02:42:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755451AbYJWGmi (ORCPT ); Thu, 23 Oct 2008 02:42:38 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:54351 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755379AbYJWGmi (ORCPT ); Thu, 23 Oct 2008 02:42:38 -0400 Date: Wed, 22 Oct 2008 23:41:57 -0700 From: Andrew Morton To: Jens Axboe Cc: Dmitri Monakhov , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH] Add block device speciffic splice write method Message-Id: <20081022234157.33d46459.akpm@linux-foundation.org> In-Reply-To: <20081023062921.GQ22217@kernel.dk> References: <1224424858-3927-1-git-send-email-dmonakhov@openvz.org> <20081020174931.GH19428@kernel.dk> <20081020181156.GI19428@kernel.dk> <20081022223928.a6ce476f.akpm@linux-foundation.org> <20081023062921.GQ22217@kernel.dk> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 23 Oct 2008 08:29:23 +0200 Jens Axboe wrote: > > But really it'd be better if the throttling happened down in > > pipe_to_file(), on a per-page basis. As it stands we can dirty an > > arbitrary number of pagecache pages without throttling. I think? > > That's pretty exactly why it isn't done in the actor, to avoid doing it > per-page. As it's going to be PIPE_BUFFERS (16) pages max, I think this > is better. > > Back in the splice early days, the balance_dirty_pages() actually showed > up in profiles when it was done on a per-page basis. So I'm reluctant to > change it :-) That's why (the misnamed) balance_dirty_pages_ratelimited() exists?