From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Bryn M. Reeves" <bmr@redhat.com>
Subject: Re: raid1 round-robin scheduler
Date: Fri, 5 Dec 2014 13:02:39 +0000
Message-ID: <20141205130239.GC16315@localhost.localdomain>
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Cc: Vasiliy Tolstov <v.tolstov@selfip.ru>
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On Fri, Dec 05, 2014 at 04:38:56PM +0400, Vasiliy Tolstov wrote:
> 2014-12-05 15:25 GMT+03:00 Vasiliy Tolstov <v.tolstov@selfip.ru>:
> > Hello. Does the somebody create scheduler for raid1 to add ability to
> > read data from all devices, for example i need to read from all
> > devices when have sequential read.
> 
> 
> I found patches in 2012 from Robert Collins, [dm-devel] Load balancing
> reads on dmraid1 (and 01) arrays
> why it not merged , does dm devel devs have plans to round-robin raid1
> reading operations ?

iirc the patches showed no measurable performance gain.

Regards,
Bryn.