Inconsistent Performance across runs

[jafioti]

Inconsistent Performance across runs

[cwfitzgerald]

You're almost certainly hitting funkyness with regards to the gpu clock speed and power saving. Generally you need to do a large-isg number of runs then take the last one. You can use the system profiler to check the power state of your chip at any one point, making sure it's on "maximum"

[jafioti]

@cwfitzgerald Is there any way to force the program to run on the maximum power mode? I'm hoping to get some sort of reliable performance out of my program

[jafioti]

These performance swings are quite drastic:

Naieve
Compute pass duration: 5455.59 ms
Naieve
Compute pass duration: 6147103160647.369 ms
Naieve
Compute pass duration: 556.000333 ms
Naieve
Compute pass duration: 9777.649291 ms
Naieve
Compute pass duration: 5117.36875 ms
Naieve
Compute pass duration: 3503.177167 ms
Naieve
Compute pass duration: 6147103130642.286 ms
Naieve
Compute pass duration: 10418.711417 ms
Naieve
Compute pass duration: 555.34225 ms
Naieve
Compute pass duration: 6833.369083 ms

I can assume the super high numbers are due to some wrapping issue, but there are still the swings between ~500 ms and ~5000 ms. I feel like it's unlikely that this is caused by the low power mode

[cwfitzgerald]

Run Instruments in Metal System Trace mode, with the target of all processes - you should see the information about the clocks and when exactly thigns are running