From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (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 554AC1DF271; Wed, 29 Oct 2025 08:55:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761728134; cv=none; b=XuinV7NTH9YgH00vxGCp7ApsE5qMKpYMHsUymSLJr2LQ5/u9rrj/FRT6KpstZvWdeT+ZkwlDeI5CJvSHAPgfUsMe3sbTM0vNp3qOTSA0JPMNkVy1DxNoxi/CNTv1IPekepggeBeVCwZGT9B9IsgyPxzQ2cIQQN8iPBgeappjO8g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761728134; c=relaxed/simple; bh=zepYc3++ebcZ2KMN9+QV/h2Vjz82C9++wv7Z2LBWOrM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=iv/q9/bDyVcDSfcfoSbaUceWk4S67PcP9+YIi9o5BMvm9/28SBxoyTxrag2uW45N66U33XSGVDtrHJYJLwQqXoMMobsXuCqGtUfWAtQjHZgCqXVhP7M/rS7bEMAgbmHhnkXirD/u6PGA+pGXJcrET4n4/OV6HlPG91U16d5QRqg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id AEDD8227A88; Wed, 29 Oct 2025 09:55:26 +0100 (CET) Date: Wed, 29 Oct 2025 09:55:26 +0100 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Kundan Kumar , Christoph Hellwig , Dave Chinner , jaegeuk@kernel.org, chao@kernel.org, viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, miklos@szeredi.hu, agruenba@redhat.com, trondmy@kernel.org, anna@kernel.org, akpm@linux-foundation.org, willy@infradead.org, mcgrof@kernel.org, clm@meta.com, amir73il@gmail.com, axboe@kernel.dk, ritesh.list@gmail.com, dave@stgolabs.net, wangyufei@vivo.com, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, gfs2@lists.linux.dev, linux-nfs@vger.kernel.org, linux-mm@kvack.org, gost.dev@samsung.com, anuj20.g@samsung.com, vishak.g@samsung.com, joshi.k@samsung.com Subject: Re: [PATCH v2 00/16] Parallelizing filesystem writeback Message-ID: <20251029085526.GA32407@lst.de> References: <20251014120845.2361-1-kundan.kumar@samsung.com> <20251022043930.GC2371@lst.de> <20251029060932.GS4015566@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-fsdevel@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: <20251029060932.GS4015566@frogsfrogsfrogs> User-Agent: Mutt/1.5.17 (2007-11-01) On Tue, Oct 28, 2025 at 11:09:32PM -0700, Darrick J. Wong wrote: > Was that with or without rtgroups? metadir/rtgroups aren't enabled by > default yet so you'd have to select that manually with mkfs.xfs -m > metadir=1. > > (and you might still not see much change because of what hch said) The real problem here is that even the inode number to AG association is just a hint, and will often go wrong on an aged file system. Now for the zoned RT device we could probably do a thread per open zone, as that is a very logical association. The problem with that right now is that we only pick the zone to write to once doing writeback, but there might be ways to lift it up. Then again zoned writeback is so little code that I can't see how it would saturate a single thread. > > --D ---end quoted text---