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Comment by tapirl

20 hours ago

The "_ [0]byte" trick has no base in my knowledge. For the author's specified example, [1024]float64 will be always allocated on one whole page, aka, always 64-byte aligned.

For "Array of Structs vs Struct of Arrays", using slices as fields is a good idea. If the purpose is to make fields allocated on their respective memory block, just use pointers instead.

> The "_ [0]byte" trick has no base in my knowledge. For the author's specified example, [1024]float64 will be always allocated on one whole page, aka, always 64-byte aligned.

You're right - I read the results I had wrong on that one. That one is slower, not faster, on both my M2 and on x86 machine.

  • My last comment has imprecision and misunderstanding.

    > ... [1024]float64 will be always allocated on one whole page, aka, always 64-byte aligned.

    if it is allocated on heap and at the start of allocated memory block.

    > For "Array of Structs vs Struct of Arrays", using slices as fields is a good idea. If the purpose is to make fields allocated on their respective memory block, just use pointers instead.

    I misunderstood it.

    It is like row-based database vs. column-based database. Both ways have their respective advantages and disadvantages.