RFR (S): JEP-142: Reduce Cache Contention on Specified Fields

Michael Barker mikeb01 at gmail.com
Sat Nov 24 00:53:24 PST 2012

>  -XX:FieldPaddingWidth=64:  3.55 +- 0.03 nsec/op
>  -XX:FieldPaddingWidth=128: 3.54 +- 0.03 nsec/op

Do you have adjacent cache line prefetching supported/enabled?  These
numbers suggest that padding to 2 cache lines doesn't provide a
significant speed up over a single cache line.  If there isn't a large
benefit to padding to 128 bytes, should be set as the default?

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