From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Ryan Subject: Re: PG recovery reservation state chart Date: Tue, 2 Oct 2012 13:40:00 -0700 Message-ID: <20121002204000.GE8206@splice> References: <20121002194858.GC8206@splice> <506B4F11.5070402@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pa0-f46.google.com ([209.85.220.46]:61644 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755287Ab2JBUkE (ORCPT ); Tue, 2 Oct 2012 16:40:04 -0400 Received: by padhz1 with SMTP id hz1so5597471pad.19 for ; Tue, 02 Oct 2012 13:40:03 -0700 (PDT) Content-Disposition: inline In-Reply-To: <506B4F11.5070402@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Josh Durgin Cc: ceph-devel@vger.kernel.org On Tue, Oct 02, 2012 at 01:31:13PM -0700, Josh Durgin wrote: > Is the local reservation taken in OSD ID order with the remote > reservations as well? What's the difference between local and remote > reservations? Are there different limits on remote and local > reservations? They come from separate pools. Each pool has a finite number of reservations, but if one pool has no more slots the other may still grant reservations. > If there's more than one possible replica to backfill from could we try > to reserve others if the first is busy instead of waiting? I think you may have your backfill terminology backward. We don't backfill from a replica, we backfill to a replica. There will never be more than one replica that needs to be backfilled to. > Why would a remote backfill reservation fail if the OSD is full > (disk space)? Backfill doesn't write to the replica, right? Or by > full, do > you mean out of reservations? If the disk on the OSD is near full we reject backfills. This change I implemented a few weeks ago and was merged last week. Backfill does write to the replica.