From: Andre Noll Subject: Re: [Bug 14830] When other IO is running sync times go to 10 to 20 minutes Date: Thu, 28 Jan 2010 11:24:09 +0100 Message-ID: <20100128102409.GR7517@skl-net.de> References: <201001251119.o0PBJDXw012169@demeter.kernel.org> <20100127130625.GQ7517@skl-net.de> <6465E5ED-8392-4929-9FD6-EFCCA7D75E0B@sun.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="uCozLMBrA/OCc/kF" Cc: Michael Godfrey , linux-ext4@vger.kernel.org To: Andreas Dilger Return-path: Received: from systemlinux.org ([83.151.29.59]:43397 "EHLO m18s25.vlinux.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752793Ab0A1KY1 (ORCPT ); Thu, 28 Jan 2010 05:24:27 -0500 Content-Disposition: inline In-Reply-To: <6465E5ED-8392-4929-9FD6-EFCCA7D75E0B@sun.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: --uCozLMBrA/OCc/kF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 12:43, Andreas Dilger wrote: > On 2010-01-27, at 06:06, Andre Noll wrote: > >On 11:19, bugzilla-daemon@bugzilla.kernel.org wrote: > >>After kill -9 of the sync run it took about 20 minutes before > >>it died. > > > >I was seeing similar behaviour on one of our servers, and changing > >the io scheduler to noop fixed things for me. So it seems to be an > >issue with cfq which is somehow triggered by ext4 but not by ext3. > > > >To change the IO scheduler, just execute > > > > echo noop > /sys/block/sda/queue/scheduler >=20 > Andre, could you please also test deadline instead of noop? Sure. I just switched to deadline and the system still feels responsive while rsync is running. With cfq a simple "ls" command took ages to complete. I'll let you know if the system becomes sluggish again after a while. Thanks Andre --=20 The only person who always got his work done by Friday was Robinson Crusoe --uCozLMBrA/OCc/kF Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) iD8DBQFLYWXJWto1QDEAkw8RAoSgAJ9JXxuzAfAhhVKNSt1zE2drd16dowCgo9qE G/tGrKsSGH3X8oKIuBIse2o= =NPRc -----END PGP SIGNATURE----- --uCozLMBrA/OCc/kF--