On 07/12/2013 06:14 AM, Ren Mingxin wrote: > Hi, Hannes: > > On 07/01/2013 10:24 PM, Hannes Reinecke wrote: >> With the original SCSI EH I got: >> # time dd if=/dev/zero of=/dev/dm-2 bs=4k count=4k oflag=direct >> 4096+0 records in >> 4096+0 records out >> 16777216 bytes (17 MB) copied, 142.652 s, 118 kB/s >> >> real 2m22.657s >> user 0m0.013s >> sys 0m0.145s >> >> With this patchset I got: >> # time dd if=/dev/zero of=/dev/dm-2 bs=4k count=4k oflag=direct >> 4096+0 records in >> 4096+0 records out >> 16777216 bytes (17 MB) copied, 52.1579 s, 322 kB/s >> >> real 0m52.163s >> user 0m0.012s >> sys 0m0.145s >> >> Test was to disable RSCN on the target port, disable the >> target port, and then start the 'dd' command as indicated. > > Do you mean disabling RSCN/port is enough? I'm afraid I couldn't > reproduce the problem by your steps. Both with and without your > patchset are the same 'dd' result: 27s. Please let me know where I > neglected or mistook: > > 1) I made a dm-multipath target 'dm-0' whose grouping policy was > failover; > 2) Disable RSCN/port via brocade fc switch: > SW300:root> portcfg rscnsupr 15 --enable; portDisable 15 > 3) Start the 'dd' command: > # time dd if=/dev/zero of=/dev/dm-0 bs=4k count=4k oflag=direct > dd: writing `/dev/sde': Input/output error > 1+0 records in > 0+0 records out > 0 bytes (0 B) copied, 27.8588 s, 0.0 kB/s > > real 0m27.860s > user 0m0.001s > sys 0m0.000s You are aware that you have to disable RSCNs on the _target_ port, right? Disabling RSCNs on the _initiator_ ports is a well-tested case, and the one which actually makes sense (and is even implemented in QLogic switches). Disabling RSCNs for the _target_ port, OTOH, has a very questionable nature (hence QLogic switches don't even allow you to do this). [ .. ] > Another question: > > I also tried to produce timeouts by modifying Yasui's module(please > see APPENDIX A): > http://www.spinics.net/lists/linux-scsi/msg35091.html > > But I got a bug with your this patchset by follwing steps(there was > not such bug without your patchset): > > # grep lpfc_template /proc/kallsyms > ffffffffa00f9240 d lpfc_template [lpfc] > # multipath -ll > ... > mpathb (36000b5d0006a0000006a14e7000c0000) dm-1 FUJITSU,ETERNUS_DX400 > size=50G features='1 queue_if_no_path' hwhandler='0' wp=rw > |-+- policy='round-robin 0' prio=130 status=active > | `- 2:0:0:1 sdf 8:80 active ready running > `-+- policy='round-robin 0' prio=130 status=enabled > `- 3:0:0:1 sdh 8:112 active ready running > # insmod scsi_tmo_mod.ko param=0xffffffffa00f9240,2:0:0:1; time dd > if=/dev/zero of=/dev/dm-1 bs=4k count=4k oflag=direct > 4096+0 records in > 4096+0 records out > 16777216 bytes (17 MB) copied, 151.194 s, 111 kB/s > > real 2m31.195s > user 0m0.004s > sys 0m0.111s > > Please see logs in APPENDIX B. Do you think this bug is irrelevant to > your patchset? > Hmm. No, sadly not. 'cancel_work_sync' cannot be called from an interrupt context; guess I'll need to convert it to delayed work. Thanks for testing; will be updating the patchset. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxx +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
