From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264261AbUHWNaT (ORCPT ); Mon, 23 Aug 2004 09:30:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264265AbUHWNaT (ORCPT ); Mon, 23 Aug 2004 09:30:19 -0400 Received: from uni02du.unity.ncsu.edu ([152.1.13.102]:43392 "EHLO uni02du.unity.ncsu.edu") by vger.kernel.org with ESMTP id S264261AbUHWNaM (ORCPT ); Mon, 23 Aug 2004 09:30:12 -0400 From: jlnance@unity.ncsu.edu Date: Mon, 23 Aug 2004 09:30:00 -0400 To: Shriram R , linux-kernel@vger.kernel.org Subject: Re: Effect of deleting executables of running programs Message-ID: <20040823133000.GA4395@ncsu.edu> References: <20040818181646.28610.qmail@web11412.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040818181646.28610.qmail@web11412.mail.yahoo.com> User-Agent: Mutt/1.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 18, 2004 at 11:16:46AM -0700, Shriram R wrote: > a) I always thought that once a job is running, the > executable is entirely loaded into memory and the > abcd.out file is no longer needed. > If so, then why does the a running job crash on > deleting abcd.out ? No, programs sections are paged in as needed, so the parts that are not running may not be in memory. That said, the Unix way of dealing with files is by reference counting. This means that you can open a file and delete it, and it is still kept around on the disk until you close it (running a program counts as having its file open). So you are susposed to be able to delete a program and running instances will not be affected. Unfortunatly, as you have discovered, NFS is kinda sorta almost like a Unix file system, but not really. You can NOT reliably access deleted files over NFS. This is the root of what is causing your bus errors. > b) To what extent can I trust that the rest of the 6-7 > jobs that are running have not been affected by this > deletion of "abcd.out" ? They are probably OK. Thanks, Jim