From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759645AbYHaV2j (ORCPT ); Sun, 31 Aug 2008 17:28:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758219AbYHaV2c (ORCPT ); Sun, 31 Aug 2008 17:28:32 -0400 Received: from casper.infradead.org ([85.118.1.10]:44856 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758059AbYHaV2b (ORCPT ); Sun, 31 Aug 2008 17:28:31 -0400 Date: Sun, 31 Aug 2008 14:28:20 -0700 From: Arjan van de Ven To: Davide Libenzi Cc: Linux Kernel Mailing List , tglx@tglx.de, Ingo Molnar , Linus Torvalds , Arnd Bergmann Subject: Re: [patch v2 0/5] Nano/Microsecond resolution for select() and poll() Message-ID: <20080831142820.40029b56@infradead.org> In-Reply-To: References: <20080831092828.13ae0279@infradead.org> Organization: Intel X-Mailer: Claws Mail 3.5.0 (GTK+ 2.12.11; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 31 Aug 2008 14:13:45 -0700 (PDT) Davide Libenzi wrote: > On Sun, 31 Aug 2008, Arjan van de Ven wrote: > > > Note: > > even though poll() (as opposed to ppoll()) only accepts milliseconds > > as userspace interface, the behavior will still improve because the > > current time no longer needs to be rounded up to the next jiffie, > > so on average a 500 microseconds behavior improvement. > > Another way to get down in the timeout resolution for newer kernels, > and still supporting the syscalls with millisec timeouts, is to use > timerfds. perhaps, but once you have to change the app you can also make it use ppoll() rather than poll().. that's a VERY minute change. -- If you want to reach me at my work email, use arjan@linux.intel.com For development, discussion and tips for power savings, visit http://www.lesswatts.org