On 8/5/21 6:50 PM, yukuai (C) wrote:
> After applying this configuration, the number of null_blk in my
> machine is about 650k(330k before). Is this still too low?

That seems low to me. If I run the attached script on a six year old
desktop with an eight core i7-4790 CPU it reports a little more than 5
million IOPS. Has kernel debugging perhaps been enabled in the kernel on
the test setup? Or is the system perhaps slowed down by security
mitigations?

> By the way, there are no performance degradation.

Please wait with drawing a conclusion until you can run a workload on
your setup of several million IOPS.

Thanks,

Bart.