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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,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 3C428C2BC61 for ; Tue, 30 Oct 2018 18:38:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6F112080A for ; Tue, 30 Oct 2018 18:38:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6F112080A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727565AbeJaDci (ORCPT ); Tue, 30 Oct 2018 23:32:38 -0400 Received: from mga17.intel.com ([192.55.52.151]:27995 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726219AbeJaDch (ORCPT ); Tue, 30 Oct 2018 23:32:37 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 30 Oct 2018 11:38:00 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,445,1534834800"; d="scan'208";a="275762646" Received: from unknown (HELO localhost.localdomain) ([10.232.112.69]) by fmsmga005.fm.intel.com with ESMTP; 30 Oct 2018 11:38:00 -0700 Date: Tue, 30 Oct 2018 12:35:39 -0600 From: Keith Busch To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCHSET v3 0/16] blk-mq: Add support for multiple queue maps Message-ID: <20181030183538.GB19483@localhost.localdomain> References: <20181030183252.17857-1-axboe@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181030183252.17857-1-axboe@kernel.dk> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 30, 2018 at 12:32:36PM -0600, Jens Axboe wrote: > This series adds support for multiple queue maps for blk-mq. > Since blk-mq was introduced, it's only support a single queue > map. This means you can have 1 set of queues, and the mapping > purely depends on what CPU an IO originated from. With this > patch set, drivers can implement mappings that depend on both > CPU and request type - and they can have multiple sets of mappings. > > NVMe is used as a proof of concept. It adds support for a separate > write queue set. One way to use this would be to limit the number > of write queues to favor reads, since NVMe does round-robin service > of queues. An easy extension of this would be to add multiple > sets of queues, for prioritized IO. > > NVMe also uses this feature to finally make the polling work > efficiently, without triggering interrupts. This both increases > performance (and decreases latency), at a lower system load. At > the same time it's more flexible, as you don't have to worry about > IRQ coalescing and redirection to avoid interrupts disturbing the > workload. This is how polling should have worked from day 1. > > This is on top of my mq-conversions branch. It can also be bound > in my mq-maps branch. Looks good to me. For the series: Reviewed-by: Keith Busch