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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 748EBC28B2E for ; Fri, 7 Mar 2025 22:17:27 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tqg01-0001sV-7d; Fri, 07 Mar 2025 17:16:57 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tqfzy-0001og-Vu for qemu-devel@nongnu.org; Fri, 07 Mar 2025 17:16:55 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tqfzx-0007lo-BD for qemu-devel@nongnu.org; Fri, 07 Mar 2025 17:16:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741385811; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=ssrIQGIGLIZjM8D3cgY9CWyZR3nU0yBcOBud7wV8Tr8=; b=EM4Gi9NUhqHbOUS8UvkFE/uOvC0avLkE2yLSZ1J1erbE13JuhlnfAg0rKKIrKi2hpAz6Dh xykLDbWbE8WRs8PrCMB8rmBLXkn+lkVD3lMzfjEZBjieOYrcNSzs8AnHPoiYWfecr2SAEB tKy1T/njcMP78ItzRJDh4Yw1QcIMtxs= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-395-206B4rWTNrahTSyqwpOtvw-1; Fri, 07 Mar 2025 17:16:48 -0500 X-MC-Unique: 206B4rWTNrahTSyqwpOtvw-1 X-Mimecast-MFC-AGG-ID: 206B4rWTNrahTSyqwpOtvw_1741385807 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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 mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 3506018001FC; Fri, 7 Mar 2025 22:16:47 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.45.226.27]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 86B2318009AE; Fri, 7 Mar 2025 22:16:44 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, stefanha@redhat.com, pbonzini@redhat.com, afaria@redhat.com, hreitz@redhat.com, qemu-devel@nongnu.org Subject: [PATCH 0/5] block: Improve writethrough performance Date: Fri, 7 Mar 2025 23:16:29 +0100 Message-ID: <20250307221634.71951-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.129.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com 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, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Write requests in writethrough mode mean that QEMU sends a separate flush request (i.e. fdatasync) after each completed write request. This is unnecessary overhead when we can just pass a flag for the write request that gives us the desired FUA semantics. Unfortunately, this made a problem in the adaptive polling algorithm apparent that would result in a performance regression in some cases with FUA support in file-posix. Therefore, adaptive polling is changed in this series, too, to avoid the regression. Kevin Wolf (5): file-posix: Support FUA writes block/io: Ignore FUA with cache.no-flush=on aio: Create AioPolledEvent aio-posix: Factor out adjust_polling_time() aio-posix: Separate AioPolledEvent per AioHandler include/block/aio.h | 5 ++- include/block/raw-aio.h | 8 +++- util/aio-posix.h | 1 + block/file-posix.c | 26 ++++++++---- block/io.c | 4 ++ block/io_uring.c | 13 +++--- block/linux-aio.c | 24 +++++++++-- util/aio-posix.c | 94 ++++++++++++++++++++++++++--------------- util/async.c | 1 - meson.build | 4 ++ 10 files changed, 125 insertions(+), 55 deletions(-) -- 2.48.1