From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: Re: v3.15 dm-mpath regression: cable pull test causes I/O hang Date: Thu, 03 Jul 2014 16:34:09 +0200 Message-ID: <53B569E1.1010405@acm.org> References: <53AD6B62.2020407@acm.org> <20140627133345.GA6150@redhat.com> <20140702220223.GA23894@redhat.com> <53B56120.8040802@acm.org> <20140703140516.GB28104@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140703140516.GB28104@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Mike Snitzer Cc: Jun'ichi Nomura , device-mapper development List-Id: dm-devel.ids On 07/03/14 16:05, Mike Snitzer wrote: > How easy would it be to replicate your testbed? Is it uniquely FIO hw > dependent? How are you simulating the cable pull tests? > > I'd love to setup a testbed that would enable me to chase this more > interactively rather than punting to you for testing. Hello Mike, The only nonstandard hardware that is required to run my test is a pair of InfiniBand HCA's and an IB cable to connect these back-to-back. The test I ran is as follows: * Let an SRP initiator log in to an SRP target system. * Start multipathd and srpd. * Start a fio data integrity test on the initiator system on top of /dev/dm-0. * From the target system simulate a cable pull by disabling IB traffic via the ibportstate command. * After a random delay, unload and reload SCST and the IB stack. This makes the IB ports operational again. * After a random delay, repeat the previous two steps. If you want I can send you the scripts I use to run this test and also the instructions that are necessary to build and install the SCST SRP target driver. Bart.