Spin Loop Hint support: Draft JEP proposal

Ivan Krylov ivan at azulsystems.com
Mon Oct 5 18:06:37 UTC 2015

>> Is this some kind of CPU.yield() (by analogy to Thread.yield())?
> I was wondering the same, it feels like a more vague (API abstraction-wise at least) architecture specific Thread.yield().
> Paul.

Thread.sleep(0), Thread.yield() and now PerformanceHints.spinLoopHint() 
are all implementation specific.
Furthermore, Intel [1] says " The execution of the next instruction is 
delayed for an implementation-specific amount of time."
Can be a nop (and is a nop on old CPUs), can be something else.

[1] - https://software.intel.com/en-us/node/524249

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