From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 3B2F726529E; Mon, 11 Aug 2025 10:52:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754909536; cv=none; b=fFeBBY56Y7cWJa1vakS+wQ3aTWMsdeRvFAKU1rYHjzd5i5mqHh/R/P212alUXhG+P8KcqLeg/lTNsEu6iwBArrhEUScgQvj5hPyDgq9byC+eGDd9B4dk9pGgbZE3Znub72Ohpa+DYygXRLHaN/zhi9Wpmvl/IFNJEGrTZ4pSwy4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754909536; c=relaxed/simple; bh=nNhBGgfo5UDY3UdB7sNOLf/9518M0X6GiNtIAdmbeFs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=AClfWHe19Fnsv1u4x4EjvSQQ3d326iS5HWr6WtGKbtjWwPb/e4NvYfIDvKO86vwCewODK2Rn8iZV/uyf6Pr+0wpDMDPHAW43Hhs55trz05F3tTgTWvk0ocnYyKUjk6ChYSMNkkWi3V3au/PajX+ZhLyO1aNzfXBLX0ssdOpGVVY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=g8SAFBFU; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="g8SAFBFU" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=r0kNG01CA6dOzzsRnPvIcMq2oWocxxH3LcP8Ljz9034=; b=g8SAFBFU7m+GF+PrkhLKmFMoVv aTlPYoUoQxhawI1WRbb6rB+6ky+vo+mzcKjFCLYDo2Wlx3Jn5gnBP9JhbBdUWweYbEkgm7ZXkQeC0 rRRJtqtfZPc49dnFElvG6m0stugCZWJbxnbsdjzlVLhly1tqCHHiY5guJcTS8a5eqVs5SncvdE5WP SkmGvWu9/bUKB8MtNWxlURk1WhT3ykWhV7WPjfGlfEcGVCs5cbgTaglajbm7SUd30A3qQxD1OTBSm o+un9nWU4NtNbgZEPj5Gy/hl9qLx/Fyn/pfIP0/RcLPalLad9zGGNh0Hq7XIqGPB322mXb2bvJH3x AKzFzeiQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1ulQ8U-00000007PQj-3cIg; Mon, 11 Aug 2025 10:52:14 +0000 Date: Mon, 11 Aug 2025 03:52:14 -0700 From: Christoph Hellwig To: Chao Yu Cc: jaegeuk@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org Subject: Re: [PATCH v3] f2fs: introduce flush_policy sysfs entry Message-ID: References: <20250807034838.3829794-1-chao@kernel.org> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250807034838.3829794-1-chao@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Thu, Aug 07, 2025 at 11:48:38AM +0800, Chao Yu wrote: > This patch introduces a new sysfs entry /sys/fs/f2fs//flush_policy > in order to tune performance of f2fs data flush flow. > > For example, checkpoint will use REQ_FUA to persist CP metadata, however, > some kind device has bad performance on REQ_FUA command, result in that > checkpoint being blocked for long time, w/ this sysfs entry, we can give > an option to use REQ_PREFLUSH command instead of REQ_FUA during checkpoint, > it can help to mitigate long latency of checkpoint. That's and odd place to deal with this. If that's a real issue it should be a block layer tweak to disable FUA, potentially with a quirk entry in the driver to disable it rather than having to touch a file system sysfs attribute. 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.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (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 09666C87FD2 for ; Mon, 11 Aug 2025 10:52:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.sourceforge.net; s=beta; h=Content-Transfer-Encoding:Content-Type:Cc: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: Subject:In-Reply-To:MIME-Version:References:Message-ID:To:From:Date:Sender: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hTk2Wm4wCXw3UIg71xiBRKm+GXxi7b8MflpB3bZmgIU=; b=XJx7MlESEVlELq9DHGHNmtUqIz ueKSQvZoXbKQr6/GZZT0fIf3bqZF0k54iZqBe2CIvIJDdAq0NqPwnqvCbix9uRZdyJ4zfS0uxcpzJ 7T0SmB1NEusDoe/QoGHrkof7HCA/DCTdpNjCi7tJlseD1GPbeuzHJB0eX5ZUPq/ZiXgU=; Received: from [127.0.0.1] (helo=sfs-ml-3.v29.lw.sourceforge.com) by sfs-ml-3.v29.lw.sourceforge.com with esmtp (Exim 4.95) (envelope-from ) id 1ulQ93-0000uV-82; Mon, 11 Aug 2025 10:52:49 +0000 Received: from [172.30.29.66] (helo=mx.sourceforge.net) by sfs-ml-3.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1ulQ8f-0000u6-He for linux-f2fs-devel@lists.sourceforge.net; Mon, 11 Aug 2025 10:52:25 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=In-Reply-To:Content-Type:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=r0kNG01CA6dOzzsRnPvIcMq2oWocxxH3LcP8Ljz9034=; b=PPwaFmOhGJ6ZmOKdsh7D7jE5hc /AP+2m7368LH+C7TFVuqL/bD1DUuIMO5oct2Fie4Xmwmx4XHj7j1LoZMchMXOrMBogeleYMcJ/ws5 xXHm6w7AQETBmgdIWwbUkLSWscI4UHwcxxnjDXDDRYAEONFa5oOgGxxhVa3xVDKjhLJY=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To :From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=r0kNG01CA6dOzzsRnPvIcMq2oWocxxH3LcP8Ljz9034=; b=Jl+aSK3XgJoQ30SdfI8NR7DHV3 P8qID4PbqIzRqeUz5tq3XgLdXvwl+qy3b2Yins2uk6E9oxbGbtICK3l95AArqVeC+Cr5rxU+pj3/c pTeO5VJW92yg13hrxw6zt2j40xNjGgX3mG/+klTc4J8QH57iP5pjLamoyYO9q0+uSzpM=; Received: from bombadil.infradead.org ([198.137.202.133]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.95) id 1ulQ8f-0005re-6P for linux-f2fs-devel@lists.sourceforge.net; Mon, 11 Aug 2025 10:52:25 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=r0kNG01CA6dOzzsRnPvIcMq2oWocxxH3LcP8Ljz9034=; b=g8SAFBFU7m+GF+PrkhLKmFMoVv aTlPYoUoQxhawI1WRbb6rB+6ky+vo+mzcKjFCLYDo2Wlx3Jn5gnBP9JhbBdUWweYbEkgm7ZXkQeC0 rRRJtqtfZPc49dnFElvG6m0stugCZWJbxnbsdjzlVLhly1tqCHHiY5guJcTS8a5eqVs5SncvdE5WP SkmGvWu9/bUKB8MtNWxlURk1WhT3ykWhV7WPjfGlfEcGVCs5cbgTaglajbm7SUd30A3qQxD1OTBSm o+un9nWU4NtNbgZEPj5Gy/hl9qLx/Fyn/pfIP0/RcLPalLad9zGGNh0Hq7XIqGPB322mXb2bvJH3x AKzFzeiQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1ulQ8U-00000007PQj-3cIg; Mon, 11 Aug 2025 10:52:14 +0000 Date: Mon, 11 Aug 2025 03:52:14 -0700 From: Christoph Hellwig To: Chao Yu Message-ID: References: <20250807034838.3829794-1-chao@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20250807034838.3829794-1-chao@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Headers-End: 1ulQ8f-0005re-6P Subject: Re: [f2fs-dev] [PATCH v3] f2fs: introduce flush_policy sysfs entry X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-block@vger.kernel.org, jaegeuk@kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On Thu, Aug 07, 2025 at 11:48:38AM +0800, Chao Yu wrote: > This patch introduces a new sysfs entry /sys/fs/f2fs//flush_policy > in order to tune performance of f2fs data flush flow. > > For example, checkpoint will use REQ_FUA to persist CP metadata, however, > some kind device has bad performance on REQ_FUA command, result in that > checkpoint being blocked for long time, w/ this sysfs entry, we can give > an option to use REQ_PREFLUSH command instead of REQ_FUA during checkpoint, > it can help to mitigate long latency of checkpoint. That's and odd place to deal with this. If that's a real issue it should be a block layer tweak to disable FUA, potentially with a quirk entry in the driver to disable it rather than having to touch a file system sysfs attribute. _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel