System_clock/high_resolution_clock

We would like to print the system time before and after executing a command (Data Transfer). Also, we would like to estimate the time taken to execute the command.

We are using the following function:

high_resolution_clock & system_clock

Would like to know how to display clock in milli/nano seconds.

Can any one please suggest?

On the CPU or the GPU? If CPU, which OS?

If CPU + Windows, look at QueryPerformanceFrequency(), or as referred to shorthand: QPC.

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