NVMe scalability issue

[Keith Busch]

On Mon, 1 Jun 2015, Ming Lin wrote:
> On Mon, Jun 1, 2015 at 4:02 PM, Keith Busch <keith.busch at intel.com> wrote:
>> There was a demo at SC'14 with a heck of a lot more NVMe drives than that,
>> and performance scaled quite linearly. Are your devices sharing PCI-e lanes?
>
> Is there a way to check it via, for example, /sys?

   # lspci -tv

>> You could try setting "cpus_allowed" on each job to the CPU's on the
>> socket local to the nvme device. That should get a measurable improvement,
>> and if your irq's are appropriately affinitized.
>
> How to know which socket is local to which nvme device?

   # cat /sys/class/nvme/nvme<#>/device/numa_node