From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hannes Reinecke <hare@suse.de>
Subject: Re: [RFC] [PATCH] add serial keyword to the weightedpath
	prioritizer
Date: Mon, 1 Aug 2016 15:18:16 +0200
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To: Christophe Varoqui <christophe.varoqui@opensvc.com>
Cc: device-mapper development <dm-devel@redhat.com>
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On 08/01/2016 02:25 PM, Christophe Varoqui wrote:
> Or we could honor arythmetic expressions like "5*alua+weightedpath",
> giving users more control about preferences (and more opportunities to
> step on their toes, sure).
>
Ugh. No.
You still would need to know which values the 'alua' (or any =

prioritizer) will be returning.
ATM there is no guarantee nor even advise which values a prioritizer =

should return. Which in itself is a good idea IMHO.

> Another idea, less invasive if possible, but less versatile :
>
> - Merge the alua prioritizer into the weightedpath prioritizer, given
> the optimized/non-optimized and other ALUA states are available in the
> path struct and have their snprint_path_* function and %wildcard.
>
Hmm. I still prefer the 'stacked prioritizer' approach, what with it =

being far more flexible.

> - Then weightedpath prio_args can be extended to support additive
> priorities, like "alua <optimized state>:<... state> 10 serial foo 20"
>
Which again would require us to define the possible return values from =

the alua (or any other handler).

Cheers,

Hannes
-- =

Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare@suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N=FCrnberg
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