From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Subject: Re: block size question Date: Wed, 18 May 2016 18:24:45 +0200 Message-ID: <573C974D.3040008@net.home> References: <573C02B3.5010501@net.home> <573C8E6E.8030008@megasoft.be> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from smtp-3.concepts.nl ([213.197.30.127]:40443 "EHLO smtp-3.concepts.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752609AbcERQZU (ORCPT ); Wed, 18 May 2016 12:25:20 -0400 Received: from [77.174.73.212] (helo=srv2.net.home) by smtp-3.concepts.nl with esmtp (Exim 4.80.1) (envelope-from ) id 1b34Hc-000ClD-Hy for linux-bcache@vger.kernel.org; Wed, 18 May 2016 18:25:16 +0200 Received: from localhost (localhost [127.0.0.1]) by srv2.net.home (Postfix) with ESMTP id 3506175846C for ; Wed, 18 May 2016 18:24:46 +0200 (CEST) Received: from srv2.net.home ([127.0.0.1]) by localhost (webmail.net.home [127.0.0.1]) (amavisd-new, port 10024) with LMTP id cbC-TwfwJ1g0 for ; Wed, 18 May 2016 18:24:46 +0200 (CEST) Received: from [192.168.1.2] (vovan.net.home [192.168.1.2]) (Authenticated sender: vovan) by srv2.net.home (Postfix) with ESMTPSA id 08941758465 for ; Wed, 18 May 2016 18:24:46 +0200 (CEST) In-Reply-To: <573C8E6E.8030008@megasoft.be> Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: linux-bcache@vger.kernel.org Killian, Thanks for your help! I think it's the best to reformat both bcache devices with block size of 4k in my case where cached device has block size of 512 and backing device 4k. Regards, Vlad. On 18/05/16 17:46, Killian De Volder wrote: > Done some testing for you: > The -B --block size has to be a a power2 of -C --block size. > > (Note: all information is about bcache1 not bcachefs if that is what you are talking about) > > Killian De Volder > > > On 18-05-16 07:50, Vlad wrote: >> Hallo, >> >> What would be the optimal block size in case if physical block sizes >> different for cache and backing devices? Can I use different block sizes >> for cache and backing devices, like: >> make-bcache --block 4k -B /dev/sdc >> make-bcache --block 512 -C /dev/sda >> >> I have a feeling that the block size should be the same and the biggest >> block size should be used, but I'd appreciate any thoughts about that. >> >> Thanks in advance, >> Vlad. >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-bcache" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html