RFR (XS): Enable UseCountedLoopSafepoints with Shenandoah

[Andrew Haley]

On 20/12/16 10:57, Aleksey Shipilev wrote:
> Since we care mostly about pause times, and not the raw throughput, it makes
> sense to enable safepoints in counted loops. This makes us much more responsive
> (as in, TTSP is lower) in many interesting scenarios.

True, but I have seen some very interesting cases where we beat G1 in
throughput.  Let's not overdo this: at the very least we need to know
how to restore throughput when running Shenandoah; all this business
of one flag affecting others can be surprising.

Andrew.