From mboxrd@z Thu Jan 1 00:00:00 1970 From: nacc@linux.vnet.ibm.com (Nishanth Aravamudan) Date: Fri, 30 Oct 2015 15:13:24 -0700 Subject: [PATCH 1/1 v3] drivers/nvme: default to 4k device page size In-Reply-To: <20151030214848.GC13904@localhost.localdomain> References: <20151026.182746.1323901353520152838.davem@davemloft.net> <20151027222010.GD7716@linux.vnet.ibm.com> <20151027223643.GA25332@localhost.localdomain> <20151027.175443.140992924519172506.davem@davemloft.net> <20151028135922.GA27909@localhost.localdomain> <20151029115536.GA28090@infradead.org> <20151029155701.GJ7716@linux.vnet.ibm.com> <20151029172043.GA8343@localhost.localdomain> <20151030213511.GK7716@linux.vnet.ibm.com> <20151030214848.GC13904@localhost.localdomain> Message-ID: <20151030221324.GM7716@linux.vnet.ibm.com> On 30.10.2015 [21:48:48 +0000], Keith Busch wrote: > On Fri, Oct 30, 2015@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