Re: [PATCH 1/1] ib_srp: Infiniband srp fast failover patch.

Karandeep Chahal
2012-05-30T14:39:46Z

Hi Dave,

As long as we get faster failover I am happy with Bart's patch.

Currently when I run IO to several luns over multipath and the preferred
path goes down, the system hangs until the IO fails over. Even ssh'ing
into the systems take 20-30 seconds. I *suspect* that is because IO is
being queued up somewhere which brings the whole system to its knees.

Thank you for looking at the patch.

Thanks
Karan

On 05/30/2012 01:06 AM, David Dillow wrote:
> On Tue, 2012-05-29 at 17:07 -0400, Karandeep Chahal wrote:
>> Subject: [PATCH] Infiniband srp fast failover patch.
> This conflicts with Bart's patches to improve failover; it will be much
> better to use his approach to block the target rather than remove it
> wholesale -- we could have lost connectivity as a transient and may get
> it back quickly if someone grabbed the wrong cable, etc.
>
> Also, we should only kill the one target on DREQ, and we already have a
> pointer to it from the CM context -- no need to search.
>
> It is a good idea to hook into the event mechanism; this is something
> I've long wanted to incorporate (as Vu did in OFED). I'm looking at
> getting Bart's series to a point I can merge it, and I'll pull in your
> ideas -- with credit -- there.
>
> Thanks,