From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752592AbbCOXpM (ORCPT ); Sun, 15 Mar 2015 19:45:12 -0400 Received: from cantor2.suse.de ([195.135.220.15]:34451 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751855AbbCOXpH (ORCPT ); Sun, 15 Mar 2015 19:45:07 -0400 Date: Mon, 16 Mar 2015 10:43:31 +1100 From: NeilBrown To: Prakash Punnoor Cc: LKML Subject: Re: udiskd high CPU usage with 4.0 git Message-ID: <20150316104331.5a2c67d8@notabene.brown> In-Reply-To: <54FDC061.2030006@punnoor.de> References: <54FC837F.8070204@punnoor.de> <20150309103056.2dea3bf6@notabene.brown> <54FDC061.2030006@punnoor.de> X-Mailer: Claws Mail 3.10.1-162-g4d0ed6 (GTK+ 2.24.25; x86_64-suse-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/_f5WXQ6f8YHWh5ZipU8YDzg"; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/_f5WXQ6f8YHWh5ZipU8YDzg Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 09 Mar 2015 16:46:41 +0100 Prakash Punnoor wro= te: > On 09.03.2015 00:30, NeilBrown wrote: > > On Sun, 08 Mar 2015 18:14:39 +0100 Prakash Punnoor = wrote: > >=20 > >> Hi, > >> > >> I noticed the udisks daemon (version 2.1.4) suddenly started using high > >> cpu (one core at 100%) with linux 4.0 git kernel. I bisected it to: > >> > >> 750f199ee8b578062341e6ddfe36c59ac8ff2dcb > >> > >> And reverting it from current master (at > >> 2cf3afcd4cbe0e32b8722fc291e9255de1b4d6c6) fixes my problem indeed. > >> > >> I attached dmesg and config from > >> 2cf3afcd4cbe0e32b8722fc291e9255de1b4d6c6 with > >> 750f199ee8b578062341e6ddfe36c59ac8ff2dcb reverted. Any more infos > >> needed? I am actually using a raid5 array, if that matters: > >> > >> Personalities : [raid6] [raid5] [raid4] > >> md127 : active raid5 sdd1[1] sdb1[3] sdc1[0] > >> 3907023872 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/= 3] > >> [UUU] > >> > >> unused devices: > >> > >> > >> The array uses systemd automount feature (x-systemd.automount). > >> > >> Please CC me, as I am not subscribed. > >> > >> > >> Regards, > >> > >> Prakash > >=20 > > Thanks for the report. > > I can't reproduce this, or see what would cause it. > >=20 > > Can you please reproduce the problem and then run > >=20 > > strace -o /tmp/udisks.trace -f -p `pidof udisksd` > >=20 > > for a few seconds, then interrupt and post the resulting '/tmp/udisks.t= race'. >=20 > Hi, attached the trace. >=20 > Thanks.=20 The significant part is: 329 poll([{fd=3D4, events=3DPOLLIN}, {fd=3D8, events=3D0}, {fd=3D9, event= s=3D0}, {fd=3D11, events=3DPOLLIN}, {fd=3D13, events=3D0}, {fd=3D12, events= =3D0}], 6, 513377) =3D 2 ([{fd=3D4, revents=3DPOLLIN}, {fd=3D12, revents=3D= POLLERR}]) repeating frequently, so fd4 and fd12 are always ready. I don't know about fd4, but fd12 is: 329 read(12, "idle\n", 1024) =3D 5 so that is .../md/sync_action It is simply always readable. I thought I had checked that, but it seems n= ot. Anyway I have a fix which I will post shortly. thanks again, NeilBrown --Sig_/_f5WXQ6f8YHWh5ZipU8YDzg Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIVAwUBVQYZIznsnt1WYoG5AQL0mw//bCD0G5jvTS9DucEy3bgSEz+4FRw+OuxR +qwwDjDCL9cyft6rgSUnSqxR1z0iKcUQJWBZdvUu5HBa+IxvMkLWmpS4Mjj/rtcR 2xEQgtx/yW+SpGECtAlYKpDBMzcZkyGG7lMTSt7FRX19cSWA6qiApbZuk1eZf4va SOvpIwLS3dW37NQ/vhoovv7T0bWtUtc+qDNjXcPuOJnFqmfRQFI6gp6uNo62g2xj KCqWB3/xzaQLaAG/vv46TdGT/5/C58mjNnhny7pjV1UHyM0c68ByUi5BAGJhOECb 8bbPzR+9pjvjAs8hJoB9Rv4eJMi1pCzZ+lF1T3TvTGdehXY/TDHcUdowkxOtkrzg Jd3cpReGgC7L81IItFG5Cp8yJ05eoSMSl/D/9tAsR0xPJXsYH/OJtnJeU7MqWWGM ui0alXI+ILBQU8P6EpSDQrRyy+tjvD9Ugjuo8gKa9LX2KufQhFZkEjcomgnzXMm1 eD9inKGKYeZ1lj+MRFeoocHHTIeB0iRa3t6kGCu/3ss/BMgP1OF1GlTiy7eR5OLj 8b4rS1P6KMLLOJEJtueS7UCGvW3ND3HlSwQE3AmiR1NRq6ZFhwMpHYuFKqMO2CZ5 MSLe9m7GQyOMqa2nVmKDJNsUmSqe/+x63uW/iid61F9WrKA4Lyygg48Zi0II+Vqp 3GdttjybYyw= =ZnxV -----END PGP SIGNATURE----- --Sig_/_f5WXQ6f8YHWh5ZipU8YDzg--