From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kasper Dieter Subject: cephfs set_layout - EINVAL Date: Fri, 9 Aug 2013 09:44:57 +0200 Message-ID: <20130809074457.GA27330@oder.mch.fsc.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from dgate20.ts.fujitsu.com ([80.70.172.51]:14586 "EHLO dgate20.ts.fujitsu.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967517Ab3HIHpB (ORCPT ); Fri, 9 Aug 2013 03:45:01 -0400 Content-Disposition: inline Sender: ceph-devel-owner@vger.kernel.org List-ID: To: "ceph-devel@vger.kernel.org" Cc: Kasper Dieter Hi, my goal is to set the 'object size' used in the distribution inside rados in an equal (or similar) way between RBD and CephFS. To set obj_size=64k in RBD I use the command: rbd create --size 1024000 --pool SSD-r2 ssd2-1T-64k --order 16 On cephfs set_layout '-s 65536' runs into EINVAL: cephfs /mnt/cephfs/fio-64k/ set_layout -p 3 -s 65536 -u 4194304 -c 1 Error setting layout: Invalid argument cephfs /mnt/cephfs/fio-64k/ set_layout -p 3 -s 65536 -u 65536 -c 1 cephfs /mnt/cephfs/fio-64k/ show_layout layout.data_pool: 3 layout.object_size: 65536 layout.stripe_unit: 65536 layout.stripe_count: 1 The man page of cephfs says ---snip--- -u --stripe_unit Set the size of each stripe -c --stripe_count Set the number of objects to stripe across -s --object_size Set the size of the objects to stripe across ---snip--- What is the equivalent command on cephfs to 'rbd create --order 16' ? Can you please give same explanation how "--stripe_unit --stripe_count --object_size" should be used in combination to achieve different layouts on CephFS directories (e.g. optimized for streaming, small sequential IOs, small random IOs) ? Thanks, -Dieter