From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757077Ab0EASnh (ORCPT ); Sat, 1 May 2010 14:43:37 -0400 Received: from fg-out-1718.google.com ([72.14.220.159]:16974 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753662Ab0EASnf (ORCPT ); Sat, 1 May 2010 14:43:35 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=taCXPa3ShA1VSHegFWJ6RMMd0Y4tgZHZ73WOrM5S3IDhuhqrnGZQ+3LWLGjcezoiyp M2JBe5nli+jRjedgGOz5k77+ezbpEtQMYSQdwxy1wurMWyaPTK7/Nv/dtQpHCa4oSZVJ KaaaIx/CekwfKzUgBbN2MuvBWu02cYc/6X68M= Message-ID: <4BDC764F.7040606@gmail.com> Date: Sat, 01 May 2010 10:43:27 -0800 From: Kent Overstreet User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.10pre) Gecko/20100422 Shredder/3.0.5pre MIME-Version: 1.0 To: Valdis.Kletnieks@vt.edu CC: linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/3] Bcache: version 4 References: <20100501001212.GA31135@moria> <63479.1272718901@localhost> In-Reply-To: <63479.1272718901@localhost> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/01/2010 05:01 AM, Valdis.Kletnieks@vt.edu wrote: > On Fri, 30 Apr 2010 16:12:13 -0800, Kent Overstreet said: > >> Most of the basic functionality is now there; the most visible thing is >> it's now correctly saving all the metadata, so you can unload a cache >> and then reload it, and everything will still be there. > > If you unload a cache and then reload it, what prevents it from serving > up now-stale data from an extent that was modified while the cache was > unloaded? > > (Telling me "Get some caffeine, it's about halfway down in patch 2" or > "We'll add that in Version 6 of the patch" are both acceptable answers" :) The plan is check if any devices are open read write on cache load and unload, and invalidate their cached data if so. Not implemented yet, though.