From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932910AbYFFVFY (ORCPT ); Fri, 6 Jun 2008 17:05:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760008AbYFFVEv (ORCPT ); Fri, 6 Jun 2008 17:04:51 -0400 Received: from deep2.securesites.net ([198.65.247.173]:1177 "EHLO deep2.securesites.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759405AbYFFVEu (ORCPT ); Fri, 6 Jun 2008 17:04:50 -0400 X-Greylist: delayed 1324 seconds by postgrey-1.27 at vger.kernel.org; Fri, 06 Jun 2008 17:04:49 EDT Date: Fri, 6 Jun 2008 14:42:08 -0600 From: Scott Wiersdorf To: Andi Kleen Cc: Balbir Singh , linux-kernel@vger.kernel.org, akpm@linux-foundation.org, matt@bluehost.com Subject: Re: [PATCH 2.6.25-4] getdelays.c: signal handling for log rotation Message-ID: <20080606204208.GB4283@perlcode.org> References: <20080605194334.GA56830@perlcode.org> <87d4muu0k2.fsf@basil.nowhere.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87d4muu0k2.fsf@basil.nowhere.org> User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 06, 2008 at 03:59:09PM +0200, Andi Kleen wrote: > Scott Wiersdorf writes: > > > This adds a USR1 signal handler to getdelays.c, which causes getdelays > > to close its logfile and reopen it (if '-w logfile' is > > specified). This is useful in situations when getdelays is running for > > a long time (i.e, the log file growing) and you need to rotate the > > logs but don't want to lose any log data. > > You could do the same by sending SIGSTOP; copy file; truncate file; SIGCONT I believe it, but you can miss a lot of important stuff between STOP and CONT, especially on a busy system. With a single handler that reopens the file, you'll miss at most one netlink datum packet, and most of the time you'll miss nothing. Scott -- Scott Wiersdorf