Thread: i9 observations
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Old 2020-10-09, 12:55   #23
henryzz
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Sep 2007
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Quote:
Originally Posted by axn View Post
Unlikely that 560K result has anything to do with memory. The i9 is a 20MB L3 part so the whole FFT should be running entirely from L3 and shouldn't be hitting RAM at all. Probably just seeing multi-threading overhead (particularly since it is such a small FFT size).

Upto 20/8 = 2.5M FFT (or slight smaller to account for other overheads) should run entirely within L3.
Is it possible the L3 bandwidth limit is being hit?
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