From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=109.224.244.106 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794747341; b=R/Bq6+Y701y7/XjmlwFjeqla4dRK2MYwhRnoFN9mBX37IqJh5PcXXbjluSc/g7F1T+X+ tu3WeKTwuf97sFlt2H0H27kX5hei+LdejWBHgN38DpsMIzIJu38ZfW4fLnq2awGGDjyN7 gM8EllgApU9WapW4/IjSQ/dpQL9MB/xsNCL5QOSdhe5J5VRqKKvn9/nJeco1oRvxm0wY8 iQuCC2HACca96DxuCaOAY/xDnv8qzGwKrOlTnvLrqjNRt8wJI45TYTM7xSCmf+A6+MZ+B kWvh7+nNZ35pugpYgbqt8Uf21TTQNrx7nJhpuXz5d4W7Z2qLE/JVbrcJIpua6mljGyQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794747341; h=DMARC-Filter:DKIM-Signature:X-Pm-Submission-Id:From:To:Cc:Subject: Date:Message-ID:X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=C72HozOP9ChGHV25Gjbk/dfVnjvNwFuPluzxe73xVgM=; b=OZMs7WedN4lFj1siNHew2VmKZEGhybNcIMTQz/s78EFf4mbQpljQNTqjVszF2yEpLqX5 6Z7B2sq/0Fe0x+N0Fndw/rsE2W7L+UXsJBSFmZcWpLoNO72LNStH9tfU3NS+H7l53kvSz qqefA21+Qjtc4gpBUaKBmPWz1zhRYHQNxG95TexsYVlfc+XzJCW2XJh9LIhEHcVhUsaiB FDaR4MUXzd6KX39k0Rp68xI79h9sNiBZ26uTFUgR4o0L2CWULikVj5cxrCWpYrrIr8RNW GHa9l2WUztVRpQXc7ppx3J/ZJbKZlL8pP9Vc1g51Ir7nLL6Ax8lJew7NB/al6HwqclA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=raidlab.org; spf=pass smtp.mailfrom=raidlab.org; dkim=pass header.d=raidlab.org header.i=@raidlab.org header.a=rsa-sha256 header.s=protonmail header.b="KuN/0ExP"; arc=none smtp.remote-ip=109.224.244.106 Received: from mail-244106.protonmail.ch (mail-244106.protonmail.ch [109.224.244.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 664FA606A31D for ; Sun, 15 Nov 2026 12:55:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 664FA606A31D Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=raidlab.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=raidlab.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=raidlab.org header.i=@raidlab.org header.a=rsa-sha256 header.s=protonmail header.b=KuN/0ExP DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=raidlab.org; s=protonmail; t=1794747338; x=1795006538; bh=C72HozOP9ChGHV25Gjbk/dfVnjvNwFuPluzxe73xVgM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References:From:To: Cc:Date:Subject:Reply-To:Feedback-ID:Message-ID:BIMI-Selector; b=KuN/0ExP6Y/Jhk8K9JYxhCXg+7z7n4GGni+9Jlcm/J0rLDKY8iU5c8ETPj+RkMDgG pgzZYkMrYDjlamVEQBFrnqGa5u9cx0YsdnYtsYkwgC5M22TXRMn1IiFGceHF50But+ RinMIUQWZpUZeoGaT0H/wSAcc97+e3hi9X8DHUQq/WIHzv0jLG4HV6e2Vl4xRGtDbD PoZq4C64z62Jgq9P7Lr/oYGYuS52zdSQdAp/gI8qBGJfXH2rmukUvBFYlt/FWgBEyM zh8jacG99kbb3exeNbBfYwmusZXoZvPcH0h4gLNsB09eM99Oq4frBYSENHI3+B6Mb3 v4pBA3OlG9VuA== X-Pm-Submission-Id: 4jS9vq52xHz2ScQ3 From: Miroslav Cimerman To: song@kernel.org, yukuai@fygo.io Cc: antosha20xx@gmail.com, magiclinan@didiglobal.com, xiao@kernel.org, neil@brown.name, tj@kernel.org, linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] md/raid5: fix write stalls when a write is queued during a drain Date: Sun, 15 Nov 2026 13:55:15 +0100 Message-ID: <20261115125515.56112-1-mc@raidlab.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20261114224636.34362-1-mc@raidlab.org> References: <20261114224636.34362-1-mc@raidlab.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Anton Gavriliuk tested the patch on the same machine as the raid6 store patch: HPE DL345 Gen11, AMD EPYC 9455, 6x PCIe 5.0 NVMe, RAID-6 4+2, chunk 512K, no bitmap, rmw_level=2, v7.4-rc2 with and without the patch, fio 4k randwrite, O_DIRECT, io_uring, 60 s, 2 runs per kernel. Slowest write and IOPS: md defaults, 1 job x QD64: without max 59.3 s / 45.1 s 128k / 124k IOPS with max 2.9 ms / 2.9 ms 129k / 126k IOPS group_thread_cnt=8, stripe_cache_size=32768, 16 jobs x QD64: without max 56.4 s / 57.5 s 472k / 474k IOPS with max 9.2 ms / 11.2 ms 483k / 479k IOPS Without the patch the slowest write of every run took 45-59 s of the 60 s. With the patch a few milliseconds. IOPS stayed the same or went up a bit. Miroslav