[concurrency-interest] help show speed-up on a trivial but manual array-map operation?

Doug Lea dl at cs.oswego.edu
Fri Mar 9 08:20:22 EST 2012


On 03/09/12 08:11, Doug Lea wrote:

> 1. Microbenchmarking artifacts: The results of the
> computations are never used so JVMs can kill some of the
> code. The attached edited version includes a "checkSum" method
> that combats this.

Plus, as I should have checked before, the use of a linear
stream of initial values is also subject to microbenchmarking
artifacts. Filling with random values instead combats this.

The main moral is that reliably measuring anything on modern
systems is harder than you'd think it should be.

-Doug
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