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=-3.9 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 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 16E29C6369E for ; Tue, 17 Nov 2020 03:28:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CC590246A4 for ; Tue, 17 Nov 2020 03:28:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hQUBcqY8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726085AbgKQD2Q (ORCPT ); Mon, 16 Nov 2020 22:28:16 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:57397 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725804AbgKQD2Q (ORCPT ); Mon, 16 Nov 2020 22:28:16 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1605583695; 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=D1JMcZkYm/tW0U9C5vpqVtKrUD6GkwmK9QMSbjO2MYE=; b=hQUBcqY8YFjGfAgvgfQ/AFe0L2FmUX4+CnjnDPU4nGbdLHKBsJRdRbL2p+12bTm5c3YCR9 cSoRbb3ln6JZfRSELVRp1DvCIopFyNXbEDtpGetZKosBDp6Xdyyu2bGVeCHnAHJCfAXNV+ 53V5qV96BTn6UXoo+E2zo5Zo0sdTgY8= 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-539-7Q3vdcxKMCakuCAFeD2ciw-1; Mon, 16 Nov 2020 22:28:11 -0500 X-MC-Unique: 7Q3vdcxKMCakuCAFeD2ciw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 09BFB802B6C; Tue, 17 Nov 2020 03:28:10 +0000 (UTC) Received: from T590 (ovpn-12-215.pek2.redhat.com [10.72.12.215]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A78655B4B0; Tue, 17 Nov 2020 03:28:00 +0000 (UTC) Date: Tue, 17 Nov 2020 11:27:56 +0800 From: Ming Lei To: Weiping Zhang Cc: Jens Axboe , Mike Snitzer , mpatocka@redhat.com, linux-block@vger.kernel.org Subject: Re: [PATCH v5 0/2] fix inaccurate io_ticks Message-ID: <20201117032756.GE56247@T590> References: <20201027045411.GA39796@192.168.3.9> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Nov 17, 2020 at 11:01:49AM +0800, Weiping Zhang wrote: > Hi Jens, > > Ping Hello Weiping, Not sure we have to fix this issue, and adding blk_mq_queue_inflight() back to IO path brings cost which turns out to be visible, and I did get soft lockup report on Azure NVMe because of this kind of cost. BTW, suppose the io accounting issue needs to be fixed, just wondering why not simply revert 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting"), and the original way had been worked for decades. Thanks, Ming