On Mon, Apr 27, 2015 at 12:59:11PM -0700, H. Peter Anvin wrote: > It really comes down to this: it seems older cores from both Intel > and AMD perform better with 66 66 66 90, whereas the 0F 1F series is > better on newer cores. > > When I measured it, the differences were sometimes dramatic.
How did you measure that? I should probably do the same on some newer AMD machines... We're using k8_nops on all AMD, even though the optimization manuals cite different NOPs on newer AMD families. Thanks. -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/