`nvmecontrol perftest -n 4 -o read -s 4096 -t 30 nvme0ns1` << here, you are reading 4K.
`nvmecontrol perftest -n 4 -o read -s 81920 -t 30 nvme0ns1` << and here, you are using only 4 threads to read 80K. The numbers are correct. max theoretical throughput is: 8GT/s*4*(128/130)/8 = 3.94 GB/s. That is also correct, but that is the top speed of the bus not the drive. Your HP EX900+ is a budget drive. The controller was never built to reach that speed. Having access to the Autobahn in Germany doesn’t suddenly make your car go 300 km/h. :) Try: nvmecontrol perftest -n 32 -o read -s 4096 -t 30 nvme0ns1 nvmecontrol perftest -n 32 -o read -s 131072 -t 30 nvme0ns1 and maybe try with -n 64. I would be interested in seeing how the IOPS and bandwidth scale with the number of outstanding requests in those drives. Thanks Abdelkader
