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 3D9A5C36010 for ; Thu, 27 Mar 2025 13:44:42 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1txnWn-0001WK-3k; Thu, 27 Mar 2025 09:44:13 -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 1txnWl-0001Ry-Av for qemu-devel@nongnu.org; Thu, 27 Mar 2025 09:44:11 -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 1txnWi-0007GY-G3 for qemu-devel@nongnu.org; Thu, 27 Mar 2025 09:44:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1743083045; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=wxM9uhtx57Ay/8dSm+yAGNTTkGkr9hHYnVk5NRRq+vQ=; b=E4GUOTZCQxD+r8PhYSMjuNGmvRxwjBkd0ss9W/nqR9aujf/8GBblKU0nTSQZ2nbsaBKGwl +ieC35xd1pN/XfOJj12XSgWqxnVIcAd+GH7wLe4raRsGZq+kVV+ccfIV9PzB6r86NIiOhl pPVXUXyWBcvZjq9ayKWCw/6nb7RqmLU= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-590-bI9x4rYxP4WEaT6fH96STg-1; Thu, 27 Mar 2025 09:44:02 -0400 X-MC-Unique: bI9x4rYxP4WEaT6fH96STg-1 X-Mimecast-MFC-AGG-ID: bI9x4rYxP4WEaT6fH96STg_1743083040 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 96B4D1800A3A; Thu, 27 Mar 2025 13:43:59 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.22.74.4]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 540051800944; Thu, 27 Mar 2025 13:43:57 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 60C4221E66C7; Thu, 27 Mar 2025 14:43:54 +0100 (CET) From: Markus Armbruster To: zoudongjie Cc: , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v3 2/2] qapi/throttle: add timeout parameter for qmp_block_set_io_throttle() In-Reply-To: <20250327123443.2250580-1-zoudongjie@huawei.com> (zoudongjie@huawei.com's message of "Thu, 27 Mar 2025 20:34:43 +0800") References: <8734ey2924.fsf@pond.sub.org> <20250327123443.2250580-1-zoudongjie@huawei.com> Date: Thu, 27 Mar 2025 14:43:54 +0100 Message-ID: <8734eytwpx.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org zoudongjie writes: > On Thu, 27 Mar 2025 09:04:51 +0100, Markus wrote: >> zoudongjie writes: >> >> > On Wed, Mar 26, 2025 at 10:53:20 +0100, Markus wrote: >> >> zoudongjie via writes: >> >> >> >> > From: Zhu Yangyang >> >> > >> >> > Calling qmp_block_set_io_throttle() will be blocked for a long time >> >> > when a network disk is configured and the network failure is just about >> >> > to occur. >> >> What other commands could similarly block? > > In theory, any command may be blocked if it calls bdrv_drained_begin(). > I did a quick check, qmp_block_resize() could similarly block, since it called > bdrv_drained_begin(), I'm going to verify it later. Please do. Should all these commands support time out? >> >> > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control >> >> > its execution duration. >> >> >> >> What's the QMP reply when a block_set_io_throttle command times out? >> > >> > The reply is: >> > {"id":"libvirt-484","error":{"class":"GenericError","desc":"Blk io limits disable timeout"}} >> >> I find the error message confusing. Suggest "command timed out". > > This message doesn't provide more details about the error, especially for developers. > How about using "command timed out: disable I/O limits" I don't get what "disable I/O limits" is trying to tell the user. Can you explain? >> >> > The default value of timeout is 0, that is infinite wait, consistent with >> >> > previous behavior. >> >> > >> >> > Signed-off-by: Zhu Yangyang >> >> [...]