Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755399Ab3JDQ2K (ORCPT ); Fri, 4 Oct 2013 12:28:10 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:41968 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754634Ab3JDQ2F (ORCPT ); Fri, 4 Oct 2013 12:28:05 -0400 Message-ID: <1380904077.1987.18.camel@dabdike.int.hansenpartnership.com> Subject: Re: Drivers: scsi: FLUSH timeout From: James Bottomley To: KY Srinivasan Cc: Eric Seppanen , "Nicholas A. Bellinger" , "linux-kernel@vger.kernel.org" , "devel@linuxdriverproject.org" , "linux-scsi@vger.kernel.org" Date: Fri, 04 Oct 2013 09:27:57 -0700 In-Reply-To: <2cc1bcb3a157418eb66bd2d91cf911c1@SN2PR03MB061.namprd03.prod.outlook.com> References: <1379705547-15028-1-git-send-email-kys@microsoft.com> <20130920203222.GA14306@kroah.com> <524180B7.7090307@gmail.com> <3413dbd7fa254fd380a84fe6d9cd87e1@SN2PR03MB061.namprd03.prod.outlook.com> <5241C9E7.2000404@cs.wisc.edu> <1380802143.19256.95.camel@haakon3.risingtidesystems.com> <2cc1bcb3a157418eb66bd2d91cf911c1@SN2PR03MB061.namprd03.prod.outlook.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.8.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2067 Lines: 51 On Fri, 2013-10-04 at 15:02 +0000, KY Srinivasan wrote: > > > -----Original Message----- > > From: Eric Seppanen [mailto:eric@purestorage.com] > > Sent: Thursday, October 03, 2013 1:49 PM > > To: Nicholas A. Bellinger > > Cc: KY Srinivasan; linux-kernel@vger.kernel.org; devel@linuxdriverproject.org; > > linux-scsi@vger.kernel.org > > Subject: Re: Drivers: scsi: FLUSH timeout > > > > On Thu, Oct 3, 2013 at 5:09 AM, Nicholas A. Bellinger > > wrote: > > > > > > On Wed, 2013-10-02 at 18:29 +0000, KY Srinivasan wrote: > > > > Ideally, I want this to be adjustable like the way we can change the I/O > > timeout. > > > > Since that has been attempted earlier and rejected (not clear what the > > reasons were), > > > > I was suggesting that we pick a larger number. James, let me know how I > > should proceed here. > > > > > > > > > > I think the objection was to making a module parameter for doing this > > > globally for all struct scsi_disk, and not the idea of making it > > > adjustable on an individual basis per-say.. > > > > > > What about adding a /sys/class/scsi_disk/$HCTL/flush_timeout..? > > > > Do I/O timeouts and flush timeouts need to be independently adjusted? > > If you're having trouble with slow operations, it seems likely to be > > across the board. > > > > Flush timeout could be defined as 2x the read/write timeout. Any > > other command-specific timeouts could be scaled the same way. > > I like this idea and would result in minimal changes. James, if it ok with you, > I could send you the patch. Depends: I still prefer the per-target override, but if the proposal is to take the existing variable timeout for the queue and have 2x that for the flush, so you plan to increase the per-device timeout with hyper-v to 90s via sysfs, then I'm OK with it. James -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/