From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757029Ab0LSRBW (ORCPT ); Sun, 19 Dec 2010 12:01:22 -0500 Received: from ist.d-labs.de ([213.239.218.44]:39408 "EHLO mx01.d-labs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752818Ab0LSRBU (ORCPT ); Sun, 19 Dec 2010 12:01:20 -0500 Date: Sun, 19 Dec 2010 18:01:09 +0100 From: Florian Mickler To: Borislav Petkov Cc: Tony Luck , Linus Torvalds , "H. Peter Anvin" , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, tglx@linutronix.de, mingo@elte.hu, greg@kroah.com, akpm@linux-foundation.org, ying.huang@intel.com, David Miller , Alan Cox , Jim Keniston , Kyungmin Park , Geert Uytterhoeven Subject: Re: [concept & "good taste" review] persistent store Message-ID: <20101219180109.3c042e43@schatten.dmk.lab> In-Reply-To: <20101219091752.GA16150@liondog.tnic> References: <4d0662e511688484b3@agluck-desktop.sc.intel.com> <4D0BEE1F.7020008@zytor.com> <20101219091752.GA16150@liondog.tnic> X-Mailer: Claws Mail 3.7.6cvs31 (GTK+ 2.20.1; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 19 Dec 2010 10:17:52 +0100 Borislav Petkov wrote: > On Sat, Dec 18, 2010 at 03:06:57PM -0800, Tony Luck wrote: > > > Doesn't that sound like the best of both worlds? > > > > It sounds like an excellent heuristic for how the platform layer > > should manage the persistent store when space is tight. But > > I think that I can still keep my /dev/pstore filesystem as a > > presentation layer to make the bits available to the user in > > a device independent way. I agree. As far as I understand, Linus concept could map nicely onto an fs: 1. marking things read: Clients can delete files as soon as they have savely scribled them down somewhere. 2. on boot the persistent storage layer init's any files in an 'archive' directory. 3. if an oops happens, the persistent storage layer shows them in the pstore-root directory. If no space is left, the persistent storage layer evicts as much oldest entries from the 'archive' as necessary. as soon as archive is empty but the pstore is full, pstore stops storing new oopses. Or not? That way, there would be some sort of journal behaviour, but also new oopses will evict old(pre-boot) oopses if necessary. maybe a kernel boot-parameter to disable deleting old oopses could be necessary in some cases. But I doubt it. Regards, Flo