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=-15.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 D2B3EC433E0 for ; Thu, 14 Jan 2021 20:03:41 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3FF2523117 for ; Thu, 14 Jan 2021 20:03:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3FF2523117 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kamp.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:47080 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l08qK-00009V-3B for qemu-devel@archiver.kernel.org; Thu, 14 Jan 2021 15:03:40 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:49862) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l08mQ-0006oL-Ah for qemu-devel@nongnu.org; Thu, 14 Jan 2021 14:59:38 -0500 Received: from kerio.kamp.de ([195.62.97.192]:47424) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l08mK-0006RD-Pk for qemu-devel@nongnu.org; Thu, 14 Jan 2021 14:59:38 -0500 X-Footer: a2FtcC5kZQ== Received: from submission.kamp.de ([195.62.97.28]) by kerio.kamp.de with ESMTPS (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256 bits)) for qemu-devel@nongnu.org; Thu, 14 Jan 2021 20:59:24 +0100 Received: (qmail 22203 invoked from network); 14 Jan 2021 19:59:28 -0000 Received: from ac14.vpn.kamp-intra.net (HELO ?172.20.250.14?) (pl@kamp.de@::ffff:172.20.250.14) by submission.kamp.de with ESMTPS (DHE-RSA-AES128-SHA encrypted) ESMTPA; 14 Jan 2021 19:59:28 -0000 Subject: Re: [PATCH 7/7] block/rbd: change request alignment to 1 byte To: dillaman@redhat.com References: <20201227164236.10143-1-pl@kamp.de> <20201227164236.10143-8-pl@kamp.de> From: Peter Lieven Message-ID: Date: Thu, 14 Jan 2021 20:59:28 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Received-SPF: pass client-ip=195.62.97.192; envelope-from=pl@kamp.de; helo=kerio.kamp.de X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.237, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Christian Theune , qemu-devel , qemu-block , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 14.01.21 um 20:19 schrieb Jason Dillaman: > On Sun, Dec 27, 2020 at 11:42 AM Peter Lieven wrote: >> since we implement byte interfaces and librbd supports aio on byte granularity we can lift >> the 512 byte alignment. >> >> Signed-off-by: Peter Lieven >> --- >> block/rbd.c | 2 -- >> 1 file changed, 2 deletions(-) >> >> diff --git a/block/rbd.c b/block/rbd.c >> index 27b4404adf..8673e8f553 100644 >> --- a/block/rbd.c >> +++ b/block/rbd.c >> @@ -223,8 +223,6 @@ done: >> static void qemu_rbd_refresh_limits(BlockDriverState *bs, Error **errp) >> { >> BDRVRBDState *s = bs->opaque; >> - /* XXX Does RBD support AIO on less than 512-byte alignment? */ >> - bs->bl.request_alignment = 512; > Just a suggestion, but perhaps improve discard alignment, max discard, > optimal alignment (if that's something QEMU handles internally) if not > overridden by the user. Qemu supports max_discard and discard_alignment. Is there a call to get these limits from librbd? What do you mean by optimal_alignment? The object size? Peter