On Tue, 2015-05-26 at 13:40 +0000, David Laight wrote: > If the JIT compiler is only changing the encoding of the constants > in the x86 instructions (rather than changing the instructions themselves) > then there is likely to me an unmeasurable change in the execution time. > For instance I don't remember there being a difference in execution time > between long and short branches - the only difference is the amount of > cache they use.
icache is precisely the matter here. In the end, it makes a difference. You could check this interesting study Ingo did recently : https://lkml.org/lkml/2015/5/19/1009 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
