From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH 01/19] freezer: don't get over-anxious while waiting Date: Fri, 02 Oct 2009 19:56:33 +0900 Message-ID: <4AC5DC61.9060900@kernel.org> References: <1254384558-1018-1-git-send-email-tj@kernel.org> <1254384558-1018-2-git-send-email-tj@kernel.org> <20091001183655.GA9995@atrey.karlin.mff.cuni.cz> <200910012304.00720.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200910012304.00720.rjw@sisk.pl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" Cc: cl@linux-foundation.org, jeff@garzik.org, pm list , rusty@rustcorp.com.au, linux-kernel@vger.kernel.org, Oren Laadan , dhowells@redhat.com, jens.axboe@oracle.com, akpm@linux-foundation.org, arjan@linux.intel.com, mingo@elte.hu List-Id: linux-pm@vger.kernel.org Hello, Pavel, Rafael. Rafael J. Wysocki wrote: > On Thursday 01 October 2009, Pavel Machek wrote: >>> Freezing isn't exactly the most latency sensitive operation and >>> there's no reason to burn cpu cycles and power waiting for it to >>> complete. msleep(10) instead of yield(). This should improve >>> reliability of emergency hibernation. >> i don't see how it improves reliability, but its probably ok. It's about battery. When emergency hibernation kicks in and something is taking a while to freeze (usually nfs does this for me) burning power waiting for it to finish is a pretty bad idea. >> Well... for hibernation anyway. I can imagine cgroup users where >> freeze is so fast that this matters. rjw cc-ed. pavel > > Thanks. I'd like to hear from the cgroup freezer people about that. Oh... didn't know that. 10ms sleeps really matter there? -- tejun