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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0EE0BC38A2D for ; Tue, 25 Oct 2022 13:12:27 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1onJfz-0004eo-7c; Tue, 25 Oct 2022 09:09:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1onJfw-00045Q-VQ for qemu-devel@nongnu.org; Tue, 25 Oct 2022 09:09:01 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1onJfs-00074i-L6 for qemu-devel@nongnu.org; Tue, 25 Oct 2022 09:08:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1666703332; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ska4LDPSbbNLgt14f1o4g8Et9Q1qLfUcsSWJcU+Nag0=; b=ZlTOV9Wls54uImh1W2KJUZTp2stBZQcAGMo+eRDzD8t8nu5ZzaCdEKSEVItMvYlVyO8cHC uZU5+oQFCtIDDTiV1IYiFhVj4N3PzOs/pVWTe5JJPzHcZNcq1PMDkGjqWmHvmawCsThpVK G19F2mh2osrMZIpzabE/f6x5ppr1EUo= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-660-FVmo-sLHOGe3LYLWZhnBXA-1; Tue, 25 Oct 2022 09:08:50 -0400 X-MC-Unique: FVmo-sLHOGe3LYLWZhnBXA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7013629DD98C; Tue, 25 Oct 2022 13:08:50 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.148]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BB7D410197; Tue, 25 Oct 2022 13:08:49 +0000 (UTC) Date: Tue, 25 Oct 2022 14:08:47 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Alex =?utf-8?Q?Benn=C3=A9e?= , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Cc: Juan Quintela , qemu-devel@nongnu.org Subject: Re: [PATCH] tests: Create fifo for test-io-channel-command Message-ID: References: <20221025105520.3016-1-quintela@redhat.com> <87mt9k6owd.fsf@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87mt9k6owd.fsf@linaro.org> User-Agent: Mutt/2.2.7 (2022-08-07) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -25 X-Spam_score: -2.6 X-Spam_bar: -- X-Spam_report: (-2.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.517, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Sender: "Qemu-devel" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org CC'ing Marc-André as original author of the change On Tue, Oct 25, 2022 at 01:57:23PM +0100, Alex Bennée wrote: > > Juan Quintela writes: > > > Previous commit removed the creation of the fifo. Without it, I get > > random failure during tests with high load, please consider > > reintroduce it. > > > > My guess is that there is a race between the two socats when we leave > > them to create the channel, better return to the previous behavior. > > > > I can't reproduce the problem when I run ./test-io-channel-command > > test alone, I need to do the make check. And any (unrelated) change > > can make it dissapear. > > I was chasing a similar problem with this test although I don't see it > timeout while running (I don't think our unit tests time out). I'm > provisionally queuing this to testing/next unless anyone objects. It won't build on Win32 since that platform lacks mkfifo. The test normally works since socat will call mknod to create the fifo. I think the problem is that we have a race condition where the client socat runs before the server socat, and so won't see the fifo. This will be where high load triggers problems. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|