From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arjan van de Ven Subject: Re: [PATCH] improve jbd fsync batching Date: Tue, 28 Oct 2008 14:44:01 -0700 Message-ID: <20081028144401.07b7546d@infradead.org> References: <20081028201614.GA21600@unused.rdu.redhat.com> <20081028213805.GC3184@webber.adilger.int> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Josef Bacik , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, rwheeler@redhat.com To: Andreas Dilger Return-path: Received: from casper.infradead.org ([85.118.1.10]:50804 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753738AbYJ1Vng (ORCPT ); Tue, 28 Oct 2008 17:43:36 -0400 In-Reply-To: <20081028213805.GC3184@webber.adilger.int> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Tue, 28 Oct 2008 15:38:05 -0600 Andreas Dilger wrote: > On Oct 28, 2008 16:16 -0400, Josef Bacik wrote: > > I also have a min() check in there to make sure we don't sleep > > longer than a jiffie in case our storage is super slow, this was > > requested by Andrew. > > Is there a particular reason why 1 jiffie is considered the "right > amount" of time to sleep, given this is a kernel config parameter and > has nothing to do with the storage? Considering a seek time in the > range of ~10ms this would only be right for HZ=100 and the wait would well... my disk does a 50 usec seek time or so.. so I don't mind ;-) in fact it sounds awefully long to me. -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org