From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E7D51C433E0 for ; Mon, 1 Jun 2020 09:09:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C52E8206E2 for ; Mon, 1 Jun 2020 09:09:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725952AbgFAJJf (ORCPT ); Mon, 1 Jun 2020 05:09:35 -0400 Received: from mx2.suse.de ([195.135.220.15]:35866 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725778AbgFAJJf (ORCPT ); Mon, 1 Jun 2020 05:09:35 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id BFFBEAC51; Mon, 1 Jun 2020 09:09:34 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 56AF61E0948; Mon, 1 Jun 2020 11:09:31 +0200 (CEST) Date: Mon, 1 Jun 2020 11:09:31 +0200 From: Jan Kara To: Martijn Coenen Cc: Jan Kara , Jaegeuk Kim , Al Viro , Jens Axboe , miklos@szeredi.hu, tj@kernel.org, linux-fsdevel@vger.kernel.org, LKML , kernel-team@android.com Subject: Re: Writeback bug causing writeback stalls Message-ID: <20200601090931.GA3960@quack2.suse.cz> References: <20200522144100.GE14199@quack2.suse.cz> <20200522153615.GF14199@quack2.suse.cz> <20200525073140.GI14199@quack2.suse.cz> <20200529152036.GA22885@quack2.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri 29-05-20 21:37:50, Martijn Coenen wrote: > Hi Jan, > > On Fri, May 29, 2020 at 5:20 PM Jan Kara wrote: > > I understand. I have written a fix (attached). Currently its under testing > > together with other cleanups. If everything works fine, I plan to submit > > the patches on Monday. > > Thanks a lot for the quick fix! I ran my usual way to reproduce the > problem, and did not see it, so that's good! I do observe write speed > dips - eg we usually sustain 180 MB/s on this device, but now it > regularly dips down to 10 MB/s, then jumps back up again. That might > be unrelated to your patch though, I will run more tests over the > weekend and report back! Thanks for testing! My test run has completed fine so I'll submit patches for review. But I'm curious what's causing the dips in throughput in your test... Honza -- Jan Kara SUSE Labs, CR