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Altera_Forum
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8 years ago

Different Kernel Executions times

Hi! I'm getting a strange thing when executing a kernel multiples times (inside a loop). The first execution always take a long time compared to the others.. Example: Number of calls: 10...
Altera_Forum's avatar
Altera_Forum
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8 years ago

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It's actually quite common in GPU programming, usually we use a warm-up kernel to get around the power-saving status so we can measure the correct runtime,

haven't encounter this on my Arria10 FPGA though.

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GPUs usually run a low-clock when idle to save power, that is why a warm-up run is required to force the GPU out of idle mode to get correct timing. However, this does not apply to FPGAs and I have certainly never encountered such behavior either.