RFR (S) 8146801: Allocating short arrays of non-constant size is slow
vladimir.x.ivanov at oracle.com
Wed Mar 2 13:05:41 UTC 2016
> I've no idea whether it would matter in real code. AFAIK, prefetchnta
> will bring the line into L1 on modern Intel. Prefetching beyond the
> small array allocation would seem undesirable as it increases
> instruction stream size for no benefit and may bring in lines that
> aren't needed at all.
Still guessing, but considering it still prefetches lines from current
TLAB, consequent allocations may benefit. Actual performance should
heavily depend on allocation rate though.
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