Thread: 69 * 2^n - 1
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Old 2014-01-14, 17:21   #22
diep's Avatar
Sep 2006
The Netherlands

67510 Posts

At the L5420 Xeon machines i have here at home, i had seen a pretty big jump in testing time moving up from roughly 2.74Mbit to 2.76 mbit

Testing times increased roughly from 6123 seconds to 7689 seconds.

Each CPU has 12 MB L2 cache.
So to speak 3MB a core
Seems it's the transform causing it, not the hardware.

Not sure about transform size internal.

If it stores 2.75M bits and assume 18 bits per double then it would require
an array sized 2.75mbits * 64 / (18 * 8 bits per byte) = 2.75 * 8 / 18 = 1.2 MB

Even double that would easily fit in L2.

At what mbit level can i again expect a big dang like that?

Is that at double this size at 5.5 Mbit?
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