Poor performance on Intel P3600 NVME driver

[Mihai Vintila]

I've tried it and are similar. Performance on this should be in the 
450/70 read/write on 4k and i'm getting 120/40.

Best regards,
Vintila Mihai Alexandru

On 1/16/2015 11:13 AM, Slawa Olhovchenkov wrote:
> On Fri, Jan 16, 2015 at 10:42:28AM +0200, Mihai Vintila wrote:
>
>> Actually seems that i've was wrong vfs.zfs.top_maxinflight does not have
>> any influence and this is confirmed by the nvmecontrol perftests.
>>    nvmecontrol perftest -n 32 -o read -s 512 -t30 nvme0ns1
>> Threads: 32 Size:    512  READ Time:  30 IO/s:  270212 MB/s:  131
>> nvmecontrol perftest -n 32 -o write -s 512 -t30 nvme0ns1
>> Threads: 32 Size:    512 WRITE Time:  30 IO/s:   13658 MB/s:    6
> I see datasheet specified performance metrics for 4K (not 512bytes) random r/w.
> Can you try this? This is may be impact write IO/s at least.
>
>> I was able to recover from the errors from previous message. They were
>> cause by the fact that i've commented hw.nvme.per_cpu_io_queues=0 in
>> loader.conf . After setting it back things got back to "slow normal"
>> Performance is half of what it should be and  issue seems to be the nvme
>> driver. I'll try it on another OS to confirm it's not a hardware setting
>> issue.