From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Mick Subject: Re: RBD layering design draft Date: Mon, 18 Jun 2012 16:07:16 -0700 Message-ID: <4FDFB4A4.1080107@inktank.com> References: <4FDB9FBB.9000807@inktank.com> <4FDF620E.7030704@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f46.google.com ([209.85.160.46]:62906 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752767Ab2FRXHU (ORCPT ); Mon, 18 Jun 2012 19:07:20 -0400 Received: by pbbrp8 with SMTP id rp8so8828119pbb.19 for ; Mon, 18 Jun 2012 16:07:19 -0700 (PDT) In-Reply-To: Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Sage Weil Cc: Josh Durgin , Tommi Virtanen , ceph-devel On 06/18/2012 11:01 AM, Sage Weil wrote: > On Mon, 18 Jun 2012, Josh Durgin wrote: >>>> $ rbd copyup pool2/child1 >>> >>> Does "copyup" make sense to everyone? Every time you say it, my brain >>> needs to flip the image inside the other way around -- I naturally >>> imagine a tree with the parent at the top, and children and >>> grandchildren down from it, but then I can't call that operation >>> "copyup" without wrecking my mental image. >>> >>> I also can't seem to google good evidence that the term would be in >>> widespread use in the enterprisey block storage world, outside of the >>> unionfs world.. What do people call the un-dedupping, un-thinning of >>> copy-on-write thin provisioning? >>> >>> "unshare"? >> >> I'm not sure what best term is, but there's probably something better than >> copyup. > > "flatten"? My mental model is stuck on the "layering" analogy, where the > child is a copy-on-write layer on top of a read-only parent. > > Someday we may want to support the ability to add a parent to an existing > image and do a sort of "dedup", so having an opposite for whatever term we > pick would be a bonus. "disown" and "adopt"? :) (actually I started as a joke, but really I kinda like that; fits with the parent-child name)