From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin McClure Subject: Re: bcachefs with cache device and backing device Date: Thu, 19 May 2016 18:18:46 -0700 Message-ID: <573E65F6.9090405@gemtalksystems.com> References: <573532E2.1040201@gemtalksystems.com> <20160513043603.GA1407@kmo-pixel> <573BD789.9030406@gemtalksystems.com> <20160518040103.GA13870@moria.home.lan> <1463547999.21115.1@mail.cooperteam.net> <20160518054124.GA1354@moria.home.lan> <573E5D24.604@gemtalksystems.com> <1463705056.3733.2@mail.cooperteam.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from 50-240-19-49-static.hfc.comcastbusiness.net ([50.240.19.49]:42161 "EHLO office-ns.gemtalksystems.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754063AbcETBSr (ORCPT ); Thu, 19 May 2016 21:18:47 -0400 In-Reply-To: <1463705056.3733.2@mail.cooperteam.net> Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: Christopher James Halse Rogers Cc: Kent Overstreet , linux-bcache@vger.kernel.org On 05/19/2016 05:44 PM, Christopher James Halse Rogers wrote: >> >> bcache format --tier 0 --bucket=512k --cache_mode=writeback \ >> -C /dev/nvme0n1 \ >> --tier 1 -C /dev/sdd1 >> >> echo /dev/sdd1 > /sys/fs/bcache/register >> echo /dev/nvme0n1 > /sys/fs/bcache/register > > You should be able to remove these steps, I think? Yes, I don't seem to need those. > >> >> mount -t bcache /dev/nvme0n1:/dev/sdd1 /mnt/whatever > > If you've pre-registered, you should be able to just > mount -t bcache /dev/nvme0n1 /mnt/whatever > or, entirely equivalently: > mount -t bcache /dev/sdd1 /mnt/whatever > Yes. Looks like I need to *either* explicitly pre-register the devices *or* specify them both in the mount command. Thanks for the clarification. The option that I'm going with for now is: bcache format --tier 0 --bucket=512k --cache_mode=writeback \ -C /dev/nvme0n1 \ --tier 1 -C /dev/sdd1 mount -t bcache /dev/nvme0n1:/dev/sdd1 /mnt/whatever since that shows me both devices in the output of "mount", reminding me and anyone else trying to figure out what's going on with this machine that both devices are involved in this filesystem. Regards, -Martin