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=-6.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 C2A49C4727F for ; Wed, 30 Sep 2020 08:43:41 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 24067206D4 for ; Wed, 30 Sep 2020 08:43:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GG//sx79" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 24067206D4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:59686 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kNXi8-0003id-4c for qemu-devel@archiver.kernel.org; Wed, 30 Sep 2020 04:43:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52210) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kNXfg-0001r8-Ap for qemu-devel@nongnu.org; Wed, 30 Sep 2020 04:41:08 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:32685) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kNXfd-0007sx-AS for qemu-devel@nongnu.org; Wed, 30 Sep 2020 04:41:07 -0400 Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601455264; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type; bh=uJzf10SJSxm+ZRTiuDYGpQsT/QyTqR8iLJnGqOGcp1c=; b=GG//sx7900aEt2s/mCp5g+9aZuOXSZ/qSrJM8n6XP5/RnECJR0FoueVXV7kcfDb3KCYFI4 bKeVzQTUbLasr32nhdB4JRtIAIxhAJNleWbFL9f/6+PhgsmOFlMCD//1hQfml2+TXVqOT2 ikdugoLL/AUrW5AIHWhUSb9o/HjT6tQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-230-Ed8cB_0UOxefbIYd3QDBdg-1; Wed, 30 Sep 2020 04:41:01 -0400 X-MC-Unique: Ed8cB_0UOxefbIYd3QDBdg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 42517839A48 for ; Wed, 30 Sep 2020 08:41:00 +0000 (UTC) Received: from localhost (ovpn-112-51.ams2.redhat.com [10.36.112.51]) by smtp.corp.redhat.com (Postfix) with ESMTP id E29825D9D3; Wed, 30 Sep 2020 08:40:59 +0000 (UTC) Date: Wed, 30 Sep 2020 09:40:59 +0100 From: "Richard W.M. Jones" To: qemu-devel@nongnu.org, kwolf@redhat.com Subject: Some comments on using qemu-storage-daemon Message-ID: <20200930084058.GA29698@redhat.com> MIME-Version: 1.0 User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=rjones@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=63.128.21.124; envelope-from=rjones@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/30 00:31:59 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.687, 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_H5=0.001, RCVD_IN_MSPIKE_WL=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" I understand that QSD is at an early stage of development and I'm sure you have plans to fix these things. Nevertheless here are my comments after trying to add an interop test with libnbd. (1) Documentation! (Or complete lack of it ...) I had to ask Kevin how to construct the command line because several things were not obvious. In particular the --blockdev parameters only make sense if you're already used to constructing blockdev parameters (and these are, separately, not well-documented). And you have to supply the parameters in a particular order on the command line, else it doesn't work. (2) There seems to be no --pid-file option, so there's no way of knowing when the server is ready to accept connections, except to start QSD and then "sleep for a bit". (3) Seems to be no support for either serving requests over stdin/stdout (qemu-nbd also lacks this, but it's common for other NBD servers); or for systemd socket activation (qemu-nbd supports this). (4) Some parameter names changed between 5.1 and upstream. I understand that you're still finalizing the command line, so this isn't a problem in itself, but others who try to use QSD will need to be aware of it. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/