slow performance of loom continuations

[Alan Bateman]

On 07/09/2018 05:47, seth lytle wrote:
> :
>
> am i using the api correctly ? i do use exceptions in other continuations,
> so UseNewCode isn't really an option for me
>
> i realize that this is an early prototype. do you have any idea what
> performance you're ultimately shooting for for this sort of loop ?
>
> is there a tradeoff between performance in these simple cases and being
> able to weave "most" production code ?
>
I skimmed through the code in your mail and you appear to be using 
continuation API correctly. It's early days in this project and too 
early to draw any conclusions on whether the approach to freezing and 
thawing the stack is the best approach or not. One performance issue is 
the current prototype is the detection of monitors in compiled frames - 
you can use -XX:-DetectLocksInCompiledFrames to workaround that issue 
temporarily which should help your test a bit (but not significantly).  
Yes, there are trade-offs when comparing it to approaches that employ 
state machines and bytecode re-writing.

-Alan