From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Bryn M. Reeves" <bmr@redhat.com>
Subject: Re: [PATCH] scsi_transport_fc: Make 'port_state' writeable
Date: Fri, 15 Mar 2013 12:37:11 +0000
Message-ID: <514315F7.4010101@redhat.com>
References: <1358262138-13378-1-git-send-email-hare@suse.de> <51421272.2000706@linux.vnet.ibm.com> <51430C4A.7090308@suse.de> <5143130F.4090702@acm.org>
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To: Bart Van Assche <bvanassche@acm.org>
Cc: Hannes Reinecke <hare@suse.de>, Steffen Maier <maier@linux.vnet.ibm.com>, linux-scsi@vger.kernel.org, Chad Dupuis <chad.dupuis@qlogic.com>, Andrew Vasquez <andrew.vasquez@qlogic.com>, James Smart <james.smart@emulex.com>, James Bottomley <jbottomley@parallels.com>, Mike Christie <michaelc@cs.wisc.edu>

On 03/15/2013 12:24 PM, Bart Van Assche wrote:
> On 03/15/13 12:55, Hannes Reinecke wrote:
>> And the LLDD is forced into error recovery which'll take _ages_ as each
>> and every command send during error recovery will time out.
>
> Hello Hannes,
>
> I'm analyzing a related but not identical issue with SRP. It would help
> if you could tell with which LLDD you ran into this issue and with which
> values of fast_io_fail_tmo and dev_loss_tmo.

Most of the cases I've seen have involved lpfc (although I don't think 
it's in any way exclusive to that LLDD). Even with very low 
fast_io_fail_timeout/dev_loss_timeout (<5/10) the eh is busy for 10m or 
longer before IO fails and multipath is able to react to the problem.

Regards,
Bryn.