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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 B5A52C04AA7 for ; Mon, 13 May 2019 19:09:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 941BA208C3 for ; Mon, 13 May 2019 19:09:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729176AbfEMTJD (ORCPT ); Mon, 13 May 2019 15:09:03 -0400 Received: from mx2.suse.de ([195.135.220.15]:56122 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728856AbfEMTJD (ORCPT ); Mon, 13 May 2019 15:09:03 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 83525AF24; Mon, 13 May 2019 19:09:02 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 95CAFDA851; Mon, 13 May 2019 21:10:03 +0200 (CEST) Date: Mon, 13 May 2019 21:10:03 +0200 From: David Sterba To: Filipe Manana Cc: dsterba@suse.cz, linux-btrfs Subject: Re: [PATCH v2] Btrfs: fix race between send and deduplication that lead to failures and crashes Message-ID: <20190513191003.GK3138@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Filipe Manana , linux-btrfs References: <20190415083018.2224-1-fdmanana@kernel.org> <20190422154342.11873-1-fdmanana@kernel.org> <20190513155607.GD3138@twin.jikos.cz> <20190513160704.GE3138@twin.jikos.cz> <20190513165853.GG3138@twin.jikos.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Mon, May 13, 2019 at 06:05:54PM +0100, Filipe Manana wrote: > On Mon, May 13, 2019 at 5:57 PM David Sterba wrote: > > > > On Mon, May 13, 2019 at 05:18:37PM +0100, Filipe Manana wrote: > > > I would leave it as it is unless users start to complain. Yes, the > > > test does this on purpose. > > > Adding such code/state seems weird to me, instead I would change the > > > rate limit state so that the messages would repeat much less > > > frequently. > > > > The difference to the state tracking is that the warning would be > > printed repeatedly, which I find unnecessary and based on past user > > feedback, there will be somebody asking about that. > > > > The rate limiting can also skip a message that can be for a different > > subvolume, so this makes it harder to diagnose problems. > > > > Current state is not satisfactory at least for me because it hurts > > testing, the test runs for about 2 hours now, besides the log bloat. The > > You mean the test case for fstests (btrfs/187) takes 2 hours for you? This is on a VM with file-backed devices, that I use for initial tests of patches before they go to other branches. It's a slow setup but helps me to identify problems early as I can run a few in parallel. I'd still like to have the run time below say 5 hours (currently it's 4). Though I can skip some thests I'd rather not due to coverage, but if there's no other way I'll have to. > For me it takes under 8 minutes for an unpatched btrfs, while a > patched btrfs takes somewhere between 1 minute and 3 minutes. This is > on VMs, with a debug kernel, average/cheap host hardware, etc. On a another host, VM with physical disks it's closer to that time, it took about 13 minutes which is acceptable.