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[bboyBladeJ]

I'm trying to measure performance of Brook+ samples shipped with the SDK, but it seems that setting BRT_RUNTIME to "cal" or "cpu" does not affect the timing information at all.

Any idea what might be wrong? We're running on a HD3870, latest drivers.

The code executes correctly and the timings obtained using Setup(0), Start(0), Stop(0) and PrintTime(0) are simply the same regardless of BRT_RUNTIME.

StreamRead and StreamWrite were excluded from measurements, only kernel call is between Start(0) and Stop(0).

Thank you.

PS. You seem to have a bug in the SDK's timer.cpp file, where PrintTime always outputs timer 0th time as opposed to timer ith time.

[michael_chu]

I'm asking our engineers about your timing problem. I'll post back when I have some information for you.

Also, thank you for reporting the bug in PrintTime. I've filed a bug report with the Brook+ team.

Michael.

[michael_chu]

The engineers just told me that the PrintTime() bug has already been fixed and will be in the next release.

By the way, just for reference, which samples did you try this on?

Thanks!

Michael.

[bboyBladeJ]

Off the top of my head, I tried haarWavelet and binary_search. I was working on my own application, but I got identical timings on that one so I tried the demos. Unfortunately, still the same thing.

Juraj

[michael_chu]

I let the engineering team know what samples you are using.

Can you try something simple? I wanted to make sure those functions were doing the right thing... can you put a sleep or something that can cause your code to wait for a second or so? I wanted to make sure the Start(0) and Stop(0) was capturing that time correctly.

Thanks!

Michael.

[bboyBladeJ]

Hey Micheal,

we just figured out yesterday night that Visual Studio needs to be restarted after changing BRT_RUNTIME. Doing this, timings came out correct.

Thanks for your time,
Juraj

[michael_chu]

Juraj,

Wonderful! 🙂 I had forgotten to remind you to restart VS whenever you changed BRT_RUNTIME.

Glad we finally got it working!

Let me know if you have any more questions!

Michael.