From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Klaube Subject: Re: bcache bug / fs freeze on heavy IO Date: Tue, 2 Sep 2014 09:37:38 +0200 (CEST) Message-ID: <1858501439.6823577.1409643458898.JavaMail.zimbra@klaube.net> References: <318258231.4483994.1408694008758.JavaMail.zimbra@klaube.net> <58978953.4484590.1408694179180.JavaMail.zimbra@klaube.net> <2025796026.5376048.1409035095370.JavaMail.zimbra@klaube.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from orion.efm.de ([195.190.148.230]:58531 "EHLO orion.efm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751295AbaIBHhl convert rfc822-to-8bit (ORCPT ); Tue, 2 Sep 2014 03:37:41 -0400 In-Reply-To: Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: Slava Pestov Cc: Kent Overstreet , linux-bcache@vger.kernel.org ----- Urspr=C3=BCngliche Mail ----- > Von: "Slava Pestov" > An: "Thomas Klaube" > CC: "Kent Overstreet" , linux-bcache@vger.kernel.o= rg > Gesendet: Sonntag, 31. August 2014 22:34:52 > Betreff: Re: bcache bug / fs freeze on heavy IO >=20 > Hi Thomas, Hi Slava, > > Aug 26 01:52:06 ubuntu kernel: [18378.656038] BUG: unable to handle= kernel > > NULL pointer dereference at 0000000000000099 >=20 > I believe this is fixed in 3.17: >=20 > http://evilpiepirate.org/git/linux-bcache.git/commit/?h=3Dbcache-dev&= id=3D2452cc89063a2a6890368f185c4b6d7d8802179e >=20 > Can you either try upgrading your kernel, or as a workaround try > increasing your bucket size. This will lower the btree depth (depth 2 > trees won't hit this problem). I upgraded to 3.17.0-rc3 and rerun the fio tests for 10 hours without a= ny=20 problems (no suspect messages in dmesg, no fs errors and no hanging tas= ks=20 or other problems). So it seems I am unable to trigger the problem in=20 3.17.0-rc3 but I will perform some more tests.... Thanx and regards Thomas Klaube