From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from resqmta-ch2-07v.sys.comcast.net ([69.252.207.39]:43991 "EHLO resqmta-ch2-07v.sys.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932554AbaJVUkB (ORCPT ); Wed, 22 Oct 2014 16:40:01 -0400 Message-ID: <5448161E.6020306@pobox.com> Date: Wed, 22 Oct 2014 13:39:58 -0700 From: Robert White MIME-Version: 1.0 To: Hugo Mills , Btrfs BTRFS Subject: Re: NOCOW and Swap Files? References: <54480ED0.9070703@pobox.com> <20141022202519.GC18164@carfax.org.uk> In-Reply-To: <20141022202519.GC18164@carfax.org.uk> Content-Type: text/plain; charset=windows-1252; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 10/22/2014 01:25 PM, Hugo Mills wrote: > The new code is the swap-on-NFS infrastructure, which indirects > swapfile accesses through the filesystem code. The reason you have to > do that with NFS is because NFS doesn't expose a block device at all, > so you can't get a list of blocks on an underlying device because > there isn't one. Indirecting the accesses through the filesystem, > however, allows us to side-step btrfs's problems with part (b) above, > and in theory gives us swapfile capability. I was not even aware there was "new code" on the matter. Is there a guide or whatever to doing this? I didn't see any mention of it in the places Google led me. --Rob