From mboxrd@z Thu Jan  1 00:00:00 1970
From: Phil Turmel <philip@turmel.org>
Subject: Re: RAID 5,6 sequential writing seems slower in newer kernels
Date: Wed, 2 Dec 2015 10:51:11 -0500
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To: Robert Kierski <rkierski@cray.com>, Dallas Clement <dallas.a.clement@gmail.com>
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On 12/02/2015 10:44 AM, Robert Kierski wrote:
> I've tried a variety of settings... ranging from 17 to 32768.
> 
> Yes.. with stripe_cache_size set to 17, I see a C/T of rmw's.  And my TP goes in the toilet -- even with the RAM disks, I get only about 30M/s.

Ok.

You mentioned you aren't using a filesystem.  How are you testing?

Phil

ps. convention on kernel.org is to trim replies and bottom-post, or
interleave.  Please do.