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=-5.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,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 E6623C433E0 for ; Mon, 18 Jan 2021 06:07:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C18C522512 for ; Mon, 18 Jan 2021 06:07:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732187AbhARGHv (ORCPT ); Mon, 18 Jan 2021 01:07:51 -0500 Received: from out30-131.freemail.mail.aliyun.com ([115.124.30.131]:46214 "EHLO out30-131.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732060AbhARGHu (ORCPT ); Mon, 18 Jan 2021 01:07:50 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R761e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0UM1RH7l_1610949976; Received: from B-D1K7ML85-0059.local(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0UM1RH7l_1610949976) by smtp.aliyun-inc.com(127.0.0.1); Mon, 18 Jan 2021 14:06:17 +0800 Subject: Re: [PATCH RFC] virtio-blk: support per-device queue depth To: Jason Wang , "Michael S. Tsirkin" Cc: virtualization@lists.linux-foundation.org, linux-block@vger.kernel.org, Jeffle Xu References: <1610942338-78252-1-git-send-email-joseph.qi@linux.alibaba.com> From: Joseph Qi Message-ID: <9a736867-d420-26eb-3ee2-42869a069640@linux.alibaba.com> Date: Mon, 18 Jan 2021 14:06:16 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi Jason, On 1/18/21 1:25 PM, Jason Wang wrote: > > On 2021/1/18 上午11:58, Joseph Qi wrote: >> module parameter 'virtblk_queue_depth' was firstly introduced for >> testing/benchmarking purposes described in commit fc4324b4597c >> ("virtio-blk: base queue-depth on virtqueue ringsize or module param"). >> Since we have different virtio-blk devices which have different >> capabilities, it requires that we support per-device queue depth instead >> of per-module. So defaultly use vq free elements if module parameter >> 'virtblk_queue_depth' is not set. > > > I wonder if it's better to use sysfs instead (or whether it has already had something like this in the blocker layer). > Thanks for quick response. Do you mean adjust /sys/block/vdX/queue/nr_requests? But current logic in virtblk_probe() is, virtblk_queue_depth is used as a saved value for first probed vdev, not purely module parameter. Thanks, Joseph