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Date: Fri, 30 Oct 2015 15:13:24 -0700
From: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
To: Keith Busch <keith.busch@intel.com>
Cc: aik@ozlabs.ru, linux-kernel@vger.kernel.org,
 linux-nvme@lists.infradead.org, Christoph Hellwig <hch@infradead.org>,
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 linuxppc-dev@lists.ozlabs.org, David Miller <davem@davemloft.net>,
 david@gibson.dropbear.id.au
Subject: Re: [PATCH 1/1 v3] drivers/nvme: default to 4k device page size
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On 30.10.2015 [21:48:48 +0000], Keith Busch wrote:
> On Fri, Oct 30, 2015 at 02:35:11PM -0700, Nishanth Aravamudan wrote:
> > Given that it's 4K just about everywhere by default (and sort of
> > implicitly expected to be, I guess), I think I'd prefer we default to
> > 4K. That should mitigate the performance impact (I'll ask our IO team to
> > do some runs, but since this impacts functionality on some hardware, I
> > don't think it's too relevant for now). Unless there are NVMe devcies
> > with a MPSMAX < 4K? 
> 
> Right, I assumed MPSMIN was always 4k for the same reason you mentioned,
> but you can hard code it like you've done in your patch.
> 
> The spec defines MPSMAX such that it's impossible to find a device
> with MPSMAX < 4k.

Great, thanks!

-Nish