Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752691AbdDEFN1 (ORCPT ); Wed, 5 Apr 2017 01:13:27 -0400 Received: from mail-vk0-f54.google.com ([209.85.213.54]:35684 "EHLO mail-vk0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752038AbdDEFNZ (ORCPT ); Wed, 5 Apr 2017 01:13:25 -0400 MIME-Version: 1.0 In-Reply-To: <8760ijiind.fsf@notabene.neil.brown.name> References: <871staffus.fsf@notabene.neil.brown.name> <20170404071033.GA25855@infradead.org> <8760ijiind.fsf@notabene.neil.brown.name> From: Ming Lei Date: Wed, 5 Apr 2017 13:13:23 +0800 Message-ID: Subject: Re: [PATCH] loop: Add PF_LESS_THROTTLE to block/loop device thread. To: NeilBrown Cc: Christoph Hellwig , Jens Axboe , linux-block , linux-mm , LKML Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 812 Lines: 28 On Wed, Apr 5, 2017 at 12:27 PM, NeilBrown wrote: > On Tue, Apr 04 2017, Christoph Hellwig wrote: > >> Looks fine, >> >> Reviewed-by: Christoph Hellwig >> >> But if you actually care about performance in any way I'd suggest >> to use the loop device in direct I/O mode.. > > The losetup on my test VM is too old to support that :-( > I guess it might be time to upgraded. > > It seems that there is not "mount -o direct_loop" or similar, so you > have to do the losetup and the mount separately. Any thoughts on I guess the 'direct_loop' can be added into 'mount' directly? but not familiar with mount utility. > whether that should be changed ? There was sysfs interface for controling direct IO in the initial submission, but looks it was reviewed out, :-) Thanks, Ming Lei