Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751312AbVLPRfq (ORCPT ); Fri, 16 Dec 2005 12:35:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751314AbVLPRfp (ORCPT ); Fri, 16 Dec 2005 12:35:45 -0500 Received: from e2.ny.us.ibm.com ([32.97.182.142]:41110 "EHLO e2.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1751312AbVLPRfp (ORCPT ); Fri, 16 Dec 2005 12:35:45 -0500 Subject: Re: [ckrm-tech] Re: [RFC][patch 00/21] PID Virtualization: Overview and Patches From: Dave Hansen To: Gerrit Huizenga Cc: Matt Helsley , Hubertus Franke , CKRM-Tech , LKML , LSE , vserver@list.linux-vserver.org, Andrew Morton , Rik van Riel , pagg@oss.sgi.com In-Reply-To: References: Content-Type: text/plain Date: Fri, 16 Dec 2005 09:35:19 -0800 Message-Id: <1134754519.19403.6.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1136 Lines: 25 On Thu, 2005-12-15 at 19:28 -0800, Gerrit Huizenga wrote: > In the pid virtualization, I would think that tasks can move between > containers as well, I don't think tasks can not be permitted to move between containers. As a simple exercise, imagine that you have two processes with the same pid, one in container A and one in container B. You wish to have them both run in container A. They can't both have the same pid. What do you do? I've been talking a lot lately about how important filesystem isolation between containers is to implement containers properly. Isolating the filesystem namespaces makes it much easier to do things like fs-based shared memory during a checkpoint/resume. If we want to allow tasks to move around, we'll have to throw out this entire concept. That means that a _lot_ of things get a notch closer to the too-costly-to-implement category. -- Dave - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/