From mboxrd@z Thu Jan 1 00:00:00 1970 From: Danny Al-Gaaf Subject: Re: limit of maximum number of rbd devices that can be mapped Date: Fri, 02 Nov 2012 13:28:14 +0100 Message-ID: <5093BC5E.10307@bisect.de> References: <507F66F1.4000509@inktank.com> <5093A78D.4060409@bisect.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from wp188.webpack.hosteurope.de ([80.237.132.195]:41664 "EHLO wp188.webpack.hosteurope.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752072Ab2KBM2S (ORCPT ); Fri, 2 Nov 2012 08:28:18 -0400 In-Reply-To: Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Sage Weil Cc: Alex Elder , Christian Huang , ceph-devel Am 02.11.2012 12:22, schrieb Sage Weil: > On Fri, 2 Nov 2012, Danny Al-Gaaf wrote: [...] >> Any news on this? We have seen the same issues here. >> >> IMO the RBD code should to something similar to some other block drivers: >> >> 1) reserve a major block number for RBD in general (or use the number >> returned from the register_blkdev call, if there is no number we can >> reserve in general for RBD, see [1]) >> >> 2) Use this major number for all RBDs on this machine and handle each >> new RBD via different minor numbers. >> >> If we can agree on this I would take a look into it and send a patch. > > We should probably do what SCSI does, where the minor for each device > jumps by 16 to leave room for partitions. That's exactly what I would propose. I wasn't sure if we really need to leave the room for the partitions, since I'm not sure if they really need to have contiguous numbers, but I guess there are some tools which expect it. > There was a thread on this a couple of weeks ago that mmy slow internet is > preventing me from finding... :) My internet connection isn't that slow here in Amsterdam ;-) ... but I couldn't find another thread about this topic. Do you remember if someone already is working on this? Danny