From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 193C1136988 for ; Mon, 20 May 2024 20:20:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716236457; cv=none; b=T6fIa0hMZKuNNfuuRgw9QmCdyDHXsgYXw+VVMW5NQjswcBTPc5RHQK9HBaioGme6J91M4xw6iKRypMTlJlRmbZFck8ltuuVAykGSky7lHv3Vs37KwnIOLNmrLMTjQ+bim7JHuknm1z3mIpbjNmzQmj6/yis4n/aZkyAJgCNX5q0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716236457; c=relaxed/simple; bh=YDCRg2Cm4geYhXAR/tMhisRKsyQxPL6umy7x/kacso4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version:Content-type; b=U+DqZZN4S59vsRkka4H7tIQYKhV3ZtYLirQr6f84srs9ZnBFVL4yScZ4rdoRGZtt3uoVQAC1EMb0hTp2SOwKsSBlkw9OD0WSNo7tPWyYI+6Hq9yvHMQSsy2ZdPtrLTZovMBZ/2RnjaaNDtbDFgKqBrHfvUR7OyctvNDwdTrABdI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=c7wIPFrt; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="c7wIPFrt" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1716236454; 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; bh=pOcNyvgHjOWe2pYYsGkhb9Oi1HGWChOiFubUg3gEQ8Y=; b=c7wIPFrt6GbjMES+gs+eEdpySAtOso//wf30wqtkYhHL8HP3xot1hY0/cW1MItfqPsWGnN EecwQoWb+KDKogP7lgkueDEhCS5Lj6Hxv4byP6xliVrr1IIR1DxOWOiv7ucawfe2/Xthbk Kn+12sfZcAw5fXOdA1lFNFmthNGMrkY= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-631-J7ENc2GXNJuxF4Elx6Z0FA-1; Mon, 20 May 2024 16:20:49 -0400 X-MC-Unique: J7ENc2GXNJuxF4Elx6Z0FA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AEBB28008A4; Mon, 20 May 2024 20:20:48 +0000 (UTC) Received: from jmeneghi.bos.com (unknown [10.22.8.193]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2460040C6CB4; Mon, 20 May 2024 20:20:48 +0000 (UTC) From: John Meneghini To: kbusch@kernel.org, hch@lst.de, sagi@grimberg.me, emilne@redhat.com Cc: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, jmeneghi@redhat.com, jrani@purestorage.com, randyj@purestorage.com, hare@kernel.org Subject: [PATCH v3 0/1] nvme: queue-depth multipath iopolicy Date: Mon, 20 May 2024 16:20:44 -0400 Message-Id: <20240520202045.427110-1-jmeneghi@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 Submitting for final review. As agreed at LSFMM I've squashed this series into one patch and addressed all review comments. Please merge this into nvme-6.10. Changes since V2: Add the NVME_MPATH_CNT_ACTIVE flag to eliminate a READ_ONCE in the completion path and increment/decrement the active_nr count on all mpath IOs - including passthru commands. Send a pr_notice when ever the iopolicy on a subsystem is changed. This is important for support reasons. It is fully expected that users will be changing the iopolicy with active IO in progress. Squashed everything and rebased to nvme-v6.10 Changes since V1: I'm re-issuing Ewan's queue-depth patches in preparation for LSFMM These patches were first show at ALPSS 2023 where I shared the following graphs which measure the IO distribution across 4 active-optimized controllers using the round-robin verses queue-depth iopolicy. https://people.redhat.com/jmeneghi/ALPSS_2023/NVMe_QD_Multipathing.pdf Since that time we have continued testing these patches with a number of different nvme-of storage arrays and test bed configurations, and I've codified the tests and methods we use to measure IO distribution All of my test results, together with the scripts I used to generate these graphs, are available at: https://github.com/johnmeneghini/iopolicy Please use the scripts in this repository to do your own testing. These patches are based on nvme-v6.9 Ewan D. Milne (1): nvme: multipath: Implemented new iopolicy "queue-depth" drivers/nvme/host/core.c | 2 +- drivers/nvme/host/multipath.c | 86 +++++++++++++++++++++++++++++++++-- drivers/nvme/host/nvme.h | 9 ++++ 3 files changed, 92 insertions(+), 5 deletions(-) -- 2.39.3