Questions about I/O queue number of NVMe device

[Yuan, Xin]

Hello,

I have question about I/O queue number in NVMe. Generally, the number of I/O queues of NVMe devices is equal to the number of CPU cores and is evenly distributed to the cores. But in some devices, I found that the I/O queue is limited and less than core number. For example, I have a 14 cores platform with Kingston NVMe. But the I/O queue number is only 8. Is it the limitation of NVMe driver or hardware? By the way, I cannot find the I/O queue number limitation on the hardware datasheet. 

Thanks,
Yuan Xin