Thread-Local Handshakes slowdown on single-cpu machines

[Karakó Miklós]

Hi Robbin,

On 4/29/20 9:45 AM, Robbin Ehn wrote:
> I have tested at least three different approaches trying to ease off the
> CPU, all off them suffered from performance regression on MP machines.
> We have internally seen this on very rare occasions on MP (we do not
> have UPs). Since this have been so rare, not trivial to fix without
> performance regression and I was under the assumption that UP were
> basically dead :), it have not been prioritized.

We have found that on VirtualBox machines used for testing where a 
single CPU was enough till the JDK was upgraded to JDK12+. Maybe the 
cheapest cloud instances are affected too (I'm not familiar with that).

Best,
Miklos