From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752830Ab0JRL6K (ORCPT ); Mon, 18 Oct 2010 07:58:10 -0400 Received: from canuck.infradead.org ([134.117.69.58]:57795 "EHLO canuck.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751818Ab0JRL6I convert rfc822-to-8bit (ORCPT ); Mon, 18 Oct 2010 07:58:08 -0400 Subject: Re: ima: use of radix tree cache indexing == massive waste of memory? From: Peter Zijlstra To: Eric Paris Cc: Eric Paris , Mimi Zohar , Christoph Hellwig , Dave Chinner , linux-kernel@vger.kernel.org, Mimi Zohar , warthog9@kernel.org, hpa@zytor.com, devel@lists.fedoraprojet.org In-Reply-To: <1287324983.2530.35.camel@localhost.localdomain> References: <20101016065206.GO4681@dastard> <20101016192027.GA6883@infradead.org> <1287295077.3020.83.camel@localhost.localdomain> <1287313332.1998.172.camel@laptop> <1287323960.1998.360.camel@laptop> <1287324983.2530.35.camel@localhost.localdomain> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Mon, 18 Oct 2010 13:57:28 +0200 Message-ID: <1287403048.29097.1553.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2010-10-17 at 10:16 -0400, Eric Paris wrote: > If instead you attack the problem from the other side and start with all > of the files we'd need some kind of freezer to so we could get the > atomicity required. We'd have to review every single file on the system > before we could be certain that the inode was correct. Maybe I'm wrong > and someone else can help me see how to solve it this way.... Well, you could use the actual freezer to freeze luserspace and then simply iterate all open files, I mean, those few sods who actually want this enabled can either pass a boot option to enable from boot or suffer the overhead on enable, right?