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 AE3E7364D6; Fri, 7 Jun 2024 05:06:44 +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=1717736805; cv=none; b=XgAcbc9IZ3n6M6W3TLoNioF5uqEMwmvMVVqdTDxXyXGF8AHtdVJiKjih1cojM6XqgluHWWeTzxqR5syv0Gw5uN3ITF1ShDF2UZB1s9/XFBl3GSp48B9M7SBCGWaxqSE4Nn5IZo2//e+bFjzpGef5xNgyNn1b/2SU2MMvEd8ngzM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717736805; c=relaxed/simple; bh=xgCIv2lNu6E4awznXLLv3uIm2OU74VkAN+UvFYeUpAo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=OARq2540wc6cCuuy4evxKKEmkJBGQ8AbC/2ZLhmHyXVH+fZhH+lL5EDnvzMAS1BFHVNCpHIScLJ9HFAOcPuIJjbZijAvZ0LXluY5iXgSsNat3gKmk/ajSvtS7LpWvAqjbKAQNsPdKCuiekcnLMkBs/s4d1IQnE6XhGkL3x+QTv4= 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=Vdz7X5ZS; 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="Vdz7X5ZS" 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=fGdVACJqTMlDqJf/M7MUWEtrjp9vLZpoiOGZVL1AWNE=; b=Vdz7X5ZS/swp+IXTJdzOD0OyIL JavKDpV+Wa5t9v9d4+KUBig8tIqAhpsi8eSrFZEz9hO1gnPztz19MBf4rAvwrLyuoyL3SUDOGJCVR dkGzClDUsBfPOns0/M383aW4QGqf4geN74U+/JDyF7tSzQ0DSSlgZAkGM8As6K1GS/KxARA/3lKtC QnHwUnlpwetYzwc68U/+/rj+RcBBVj8LZjs9tdc1ARfcV5CORxO1buf7ZRp4WsjZcWFaZkh/2LcR8 U4dji0UGhkxRodl6yN1Q4ZDeMLDfKN53C14V76xQoIFU9yZpS9hNAEcSLA2pOfKOSU0kR93YsumpR xuIaeyNw==; Received: from hch by bombadil.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1sFRoI-0000000CRzN-2vYD; Fri, 07 Jun 2024 05:06:42 +0000 Date: Thu, 6 Jun 2024 22:06:42 -0700 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Christoph Hellwig , zlang@redhat.com, fstests@vger.kernel.org, linux-xfs@vger.kernel.org, guan@eryu.me Subject: Re: [PATCHSET 3/3] xfsprogs: scale shards on ssds Message-ID: References: <171744525781.1532193.10780995744079593607.stgit@frogsfrogsfrogs> <20240605005636.GI52987@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: fstests@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: <20240605005636.GI52987@frogsfrogsfrogs> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Jun 04, 2024 at 05:56:36PM -0700, Darrick J. Wong wrote: > Not much other than the AG[IF] and log grant heads becoming less hot. > That pushes the bottlenecks to the storage device, which indeed is about > 8 per device. More if you can raid0 them. > > *Fortunately* for metadata workloads the logging code is decent about > deduplicating repeated updates, so unless you're doing something truly > nasty like synchronous direct writes to a directory tree with parent > pointers that is being modified heavily, it takes some effort to > overload the ssd. > > (Or a crappy ssd, I guess. Maybe I'll pull out the 860 QVO and see how > it does.) Ok. I'm also a little worried about creating lots of AGs for tiny file systems. Then again I've not actually been able to find the code yet which I should probably look at first.