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A comment on Memory access on the Apple M1 processor. Parent comment

Re:Memory access on the Apple M1 processor by celrod on Thursday January 07, 2021 @05:20AM (#25669396)
Yeah, that is strange. Why was it so slow? Trying on a desktop with a 7900X, I get

  N = 1000000000, 953.7 MB
  starting experiments.
  two  : 17.7 ns
  two+  : 19.1 ns
  three: 26.4 ns
  bogus 1422321000
This is again close to 50% slower than your time, but nearly twice as fast. I'll try again on the laptop and make sure I don't have other processes running.
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Re:Memory access on the Apple M1 processor by gspr on Thursday January 07, 2021 @06:55AM (#25670012)
Strange. I suppose the compiler shouldn't matter much here, right? At any rate, I'm using GCC 10.2.1.
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Re:Memory access on the Apple M1 processor by celrod on Thursday January 07, 2021 @07:33AM (#25670291)
I'm using gcc 10.2.0. I tried clang 11 and got more or less the same thing, so it doesn't seem to make much of a difference.

Neither did messing with flags, like (I tried -fno-semantic-interposition -march=native and a few others).

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