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=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, 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 6C1DBC433E0 for ; Wed, 13 Jan 2021 15:31:21 +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 CADFE23102 for ; Wed, 13 Jan 2021 15:31:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CADFE23102 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]:55276 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kzi7D-0005FE-LP for qemu-devel@archiver.kernel.org; Wed, 13 Jan 2021 10:31:19 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:38652) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kzhwA-0002pR-DD for qemu-devel@nongnu.org; Wed, 13 Jan 2021 10:19:54 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:35830) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kzhw7-0002e0-Ax for qemu-devel@nongnu.org; Wed, 13 Jan 2021 10:19:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610551187; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JKrsytn2j+V5ww9QeU4E4x3uuzpX6a1GgF/MLRt5Kaw=; b=VP/1Rkof3cwDRF9xK9ZAf3sUaGK/vX4Fpj1NDwhghxEz537k75MIDdeTcDWlI87bJgOjuG BoxfL/fyNI+Q2hT6IrApUDT47Js5pAKzaPOUxDmhXNeKSInG1FijZmYLKVz7wbN+TcOVFp PPK21Z6XRaxhPLNJQZE5parMJ9/ttdU= 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-360-VOzmcZ-DPHuQZvRoe67HLw-1; Wed, 13 Jan 2021 10:19:46 -0500 X-MC-Unique: VOzmcZ-DPHuQZvRoe67HLw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0EAD19CC03; Wed, 13 Jan 2021 15:19:45 +0000 (UTC) Received: from dresden.str.redhat.com (ovpn-113-103.ams2.redhat.com [10.36.113.103]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E29EF60D08; Wed, 13 Jan 2021 15:19:43 +0000 (UTC) Subject: Re: [PATCH 0/7] iotests/129: Fix it To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20210113140616.150283-1-mreitz@redhat.com> <746f2be4-4093-fcff-fddb-60b0cae74c31@virtuozzo.com> From: Max Reitz Message-ID: Date: Wed, 13 Jan 2021 16:19:42 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <746f2be4-4093-fcff-fddb-60b0cae74c31@virtuozzo.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.25, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=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: , Cc: Kevin Wolf , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 13.01.21 15:31, Vladimir Sementsov-Ogievskiy wrote: > 13.01.2021 17:06, Max Reitz wrote: >> Hi, >> >> There are some problems with iotests 129 (perhaps more than these, but >> these are the ones I know of): >> >> 1. It checks @busy to see whether a block job is still running; however, >>     block jobs tend to unset @busy all the time (when they yield). >>     [Fixed by patch 3] >> >> 2. It uses blockdev throttling, which quite some time ago has been moved >>     to the BB level; since then, such throttling will no longer affect >>     block jobs.  We can get throttling to work by using a throttle filter >>     node. >>     [Fixed by patch 4] >> >> 3. The mirror job has a large buffer size by default.  A simple drain >>     may lead to it making significant process, which is kind of >>     dangerous, because we don’t want the job to complete. > > Not quite clear to me. iotest 129 wants to mirror 128M of data. Mirror by > default will have 1M chunk size and maximum of 16 parallel requests. So > with > throttling (even if throttling can't correctly handle parallel requests) > we will not exceed 16M of progress.. Why we need limiting buffer size? It does exceed 16M of progress; without the limit, I generally see something between 16M and 32M. Now, that still is below 128M, but it’s kind of in the same magnitude. I don’t feel comfortable with that, especially given it’s so easy to limit it to much less (buf_size=64k makes the job proceed to 128k). Also, maybe the default is increased in the future. Increasing the chunk size by 4 would mean that it might be possible to reach 128M. I find not relying on the default better. Max