From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: init_timer_deferrable conversion Date: Mon, 17 Dec 2007 09:00:00 -0800 Message-ID: <20071217090000.64499fba@deepthought> References: <20071217095504.b02241ee.dada1@cosmosbay.com> <20071217152943.10470215.dada1@cosmosbay.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "parag.warudkar@gmail.com" , linux-kernel@vger.kernel.org, David Miller , "netdev@vger.kernel.org" To: Eric Dumazet Return-path: In-Reply-To: <20071217152943.10470215.dada1@cosmosbay.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Mon, 17 Dec 2007 15:29:43 +0100 Eric Dumazet wrote: > On Mon, 17 Dec 2007 09:55:04 +0100 > Eric Dumazet wrote: > > > On Sun, 16 Dec 2007 22:00:23 -0500 (EST) > > Parag Warudkar wrote: > > > > > In my quest to get the wake-ups from idle per second down to bare minimum, > > > I noticed 3 places in the kernel that could benefit from > > > using init_timer_deferrable() instead of init_timer() - > > > > > > a) drivers/net/sky2.c - watchdog_timer. This was showing up high on > > > Powertop's list of things that cause routine wakeups from idle. After > > > converting to init_timer_deferrable() the wakeups went down and this one > > > no longer shows up in powertop's list. 25% reduction. This surprises me because it is a 1 hz timer and uses round_jiffies() in the current kernel. -- Stephen Hemminger