From mboxrd@z Thu Jan 1 00:00:00 1970 From: Francis Moreau Subject: Re: [PATCH] bcache: fix uninterruptible sleep in writeback thread Date: Fri, 05 Sep 2014 09:08:09 +0200 Message-ID: <54096159.6060602@gmail.com> References: <1398981150-27765-1-git-send-email-sp@daterainc.com> <537112A5.6040709@kieser.ca> <53747499.3070000@gmail.com> <5374F9D2.8020209@kernel.dk> <538C8539.1060607@gmail.com> <53D20795.60404@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-lb0-f182.google.com ([209.85.217.182]:61081 "EHLO mail-lb0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751013AbaIEHFq (ORCPT ); Fri, 5 Sep 2014 03:05:46 -0400 In-Reply-To: <53D20795.60404@gmail.com> Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: Jens Axboe Cc: Peter Kieser , kmo@daterainc.com, linux-bcache@vger.kernel.org, LKML On 07/25/2014 09:30 AM, Francis Moreau wrote: > Hi, > > On 06/02/2014 04:07 PM, Francis Moreau wrote: >> Hello, >> >> On 05/15/2014 07:30 PM, Jens Axboe wrote: >>> On 05/15/2014 02:02 AM, Francis Moreau wrote: >>>> Hello Jens, >>>> >>>> On 05/12/2014 08:27 PM, Peter Kieser wrote: >>>>> >>>>> On 2014-05-05 3:30 PM, Nikolay Amiantov wrote: >>>>>> 2014-05-02 1:52 GMT+04:00 Slava Pestov : >>>>>>> There were two issues here: >>>>>>> >>>>>>> - writeback thread did not start until the device first became dirty >>>>>>> - writeback thread used uninterruptible sleep once running >>>>>>> >>>>>>> Without this patch I see kernel warnings printed and a load average of >>>>>>> 1.52 after booting my test VM. With this patch the warnings are gone and >>>>>>> the load average is near 0.00 as expected. >>>>>> I've tried this patch and it has indeed fixed [1]! Thanks! >>>>>> >>>>>> [1]: https://bugzilla.kernel.org/show_bug.cgi?id=69471 >>>>> >>>>> Kent, >>>>> >>>>> Could you please review this patch, and have it pushed upstream? >>>>> >>>> >>>> Would it be possible to merge this patch directly before 3.15 is being >>>> released since kent don't seem to care about bugs in bcache or maybe he >>>> does but very selectively ? >>>> >>>> Also it would be great that stable trees will be fixed. >>>> >>>> Eventually I would suggest to mark bcache as an experimental thing since >>>> it's really not ready for production, just take a look at the bcache >>>> mailing list to see why. At least people won't be disappointed when >>>> they'll use bcache and see ton of koops. >>> >>> I'd really like to get Kent to weigh in on this. Sometimes it appears >>> straightforward to switch from uninterruptible to interruptible sleep, >>> but then signals get in the way. >>> >> >> Any progress ? >> > > still present on 3.15.5-2-ARCH :-/ > still present on 3.14.17 :-/