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=-4.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,URIBL_SBL,URIBL_SBL_A,USER_AGENT_MUTT autolearn=ham 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 9BDADC48BD3 for ; Wed, 26 Jun 2019 20:27:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6967A2085A for ; Wed, 26 Jun 2019 20:27:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="POv1IyE+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726339AbfFZU1K (ORCPT ); Wed, 26 Jun 2019 16:27:10 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:40937 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726227AbfFZU1K (ORCPT ); Wed, 26 Jun 2019 16:27:10 -0400 Received: by mail-pl1-f196.google.com with SMTP id a93so2045489pla.7; Wed, 26 Jun 2019 13:27:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=x1o8oqi0CP9ZDnGVZ99akUd6mY/E2omAq/EbskrFW4k=; b=POv1IyE+sfM8PtylMEWG9x0KHLapZZmKG9O21FYbI6DJsX5YyUowJrGlqsd1brIdG8 4ooVgaj5bl5g67fjcD008OmeeshHnFYPER80FNuf5bYHxde/ukJ7bWPpS8NczoyEc+cd CKv88keWcLtmuhtiNaZoX+rSSEGKhfYIcDgDEeWjODEkilqjwNyropymwYsdONJxg/BT RNVNSIq/3Dm6bgbcxL3pgXBZ/PJQDE9Y849OPSdGMAR8sKJdGdQE52In7DcwfdXdT/zY 0kLbMrXm0RsqOhLX7c87vpo1H5eqgA6gd/xXSJomam4kbPKHTDP711I23q8T80n26mkx 3q8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=x1o8oqi0CP9ZDnGVZ99akUd6mY/E2omAq/EbskrFW4k=; b=SHDq5fb5Plw6aHWd+FfXsFUSEk/6rSZjetOcMVtIOen3dqZkZBI5jyWCEJd5z5FeF0 cCRIo5Jxqj9iD/hgtEtR1pRGWmVTa3R/vKWkWrDksZT6I4J6wuGywRJzj6DoLcOsdVAJ ZnOUn8R3sQ0CVFvjHBXdQNjEQWZbivu/VRj/npDBuYXVrwawLoVMnINfs0A1A/qdqBis rturGjulM3NxeQwDNS3hbVWMj0kN60NWpaK0B+Sail50pGTROjVYeYU4GPa67IOpEVKU TBGJas6eTX/m2XOdtCTINLn1LHWuJwlUX6yspQdo0AxsHhnlwMSEQwO7YPuuAJhtL+Jr TNOA== X-Gm-Message-State: APjAAAUjSExevr7Kh32l3zgULNXHwSjWdpKwM+IdeLx6q6W2s89y8jS5 PEAn18fIVr0HlcPtgUiecmc= X-Google-Smtp-Source: APXvYqyjymNoPT4b92sWLExLPDZZq/X+c5U+Nyf00E2YjebGqOGMookCtAi+tYDjxEy8W4ninii9dg== X-Received: by 2002:a17:902:9b81:: with SMTP id y1mr7962559plp.194.1561580829862; Wed, 26 Jun 2019 13:27:09 -0700 (PDT) Received: from localhost ([123.213.206.190]) by smtp.gmail.com with ESMTPSA id p27sm83702pfq.136.2019.06.26.13.27.08 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 26 Jun 2019 13:27:09 -0700 (PDT) Date: Thu, 27 Jun 2019 05:27:06 +0900 From: Minwoo Im To: Weiping Zhang Cc: Weiping Zhang , Jens Axboe , Tejun Heo , Christoph Hellwig , Bart Van Assche , keith.busch@intel.com, linux-block@vger.kernel.org, cgroups@vger.kernel.org, linux-nvme@lists.infradead.org, Minwoo Im Subject: Re: [PATCH v3 3/5] nvme-pci: rename module parameter write_queues to read_queues Message-ID: <20190626202706.GC4934@minwooim-desktop> References: <20190624200445.GB6526@minwooim-desktop> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 19-06-25 22:48:57, Weiping Zhang wrote: > Minwoo Im 于2019年6月25日周二 上午6:00写道： > > > > On 19-06-24 22:29:19, Weiping Zhang wrote: > > > Now nvme support three type hardware queues, read, poll and default, > > > this patch rename write_queues to read_queues to set the number of > > > read queues more explicitly. This patch alos is prepared for nvme > > > support WRR(weighted round robin) that we can get the number of > > > each queue type easily. > > > > > > Signed-off-by: Weiping Zhang > > > > Hello, Weiping. > > > > Thanks for making this patch as a separated one. Actually I'd like to > > hear about if the origin purpose of this param can be changed or not. > > > > I can see a log from Jens when it gets added her: > > Commit 3b6592f70ad7("nvme: utilize two queue maps, one for reads and > > one for writes") > > It says: > > """ > > NVMe does round-robin between queues by default, which means that > > sharing a queue map for both reads and writes can be problematic > > in terms of read servicing. It's much easier to flood the queue > > with writes and reduce the read servicing. > > """ > > > > So, I'd like to hear what other people think about this patch :) > > > > This patch does not change its original behavior, if we set read_queue > greater than 0, the read and write request will use different tagset map, > so they will use different hardware queue. Yes, that's why I want to hear some comments for this change from other people. I'm not against this change, though.