From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willem Jan Withagen Subject: Re: Hard to debug problem with ceph_erasure_code Date: Fri, 1 Apr 2016 14:22:24 +0200 Message-ID: <56FE6800.7050407@digiware.nl> References: <56FD5A15.1080507@digiware.nl> <20160401051205.GA29567@gmail.com> <56FE4098.8000209@digiware.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from smtp.digiware.nl ([31.223.170.169]:54410 "EHLO smtp.digiware.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752597AbcDAMW4 (ORCPT ); Fri, 1 Apr 2016 08:22:56 -0400 In-Reply-To: <56FE4098.8000209@digiware.nl> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Mykola Golub Cc: Ceph Development On 1-4-2016 11:34, Willem Jan Withagen wrote: > On 1-4-2016 07:12, Mykola Golub wrote: >> On Thu, Mar 31, 2016 at 07:10:45PM +0200, Willem Jan Withagen wrote: >> >>> Does anybody have suggestions as how to track/debug this? >> >> valgrind? >> >=20 > Yup, tried that one, but it is sort of hard to find an intermittent > erroneous write. I tried --track-addr=3D But most = of > the time it is only written at exact the code line it is supposed to= be > written. So no info there. >=20 > So perhaps I need a different set of tests? >=20 > On average I need about 600 runs to catch one SIGSEGV. >=20 > BTW: tried it on 2 FreeBSD systems, and on both the behaviour is > identical. So it has got to be the code. And since 65000 runs on Linu= x > give no errors, it is also typical for the combo > FreeBSD/Clang/FreeBSD-packages. And it gets even weirder. Clang allows to use of AddressSanitizer ( https://github.com/google/sanitizers/wiki/AddressSanitizer ) So i've compiled all of ceph with -fsanitize=3Daddress -fno-omit-frame-pointer And now I've already logged 50.000 runs without crashes. =46eels a lot like Schr=F6dinger's cat.... --WjW -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html