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A comment on Composable multi-threaded parallelism in Julia. Parent comment

Re:Composable multi-threaded parallelism in Julia by leiroigh on Tuesday July 23, 2019 @08:41PM (#20511436)
Big difference is that Cilk appears to typically synchronize on function return, while julia needs an explicit wait/fetch (there is also a @sync macro). That is, spawn/wait can be matched from the AST in cilk, while julia demands that the user communicates and stores a reference to the started task for later waiting.

It is easy to forget to wait on a task, or even lose reference to it. The current scheduler will typically execute this task quickly, even if nobody ever waits on it; until load changes and you have races everywhere. There are currently no warnings comparable to Python's "RuntimeWarning: coroutine foo was never awaited".

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Re:Composable multi-threaded parallelism in Julia by jakear on Wednesday July 24, 2019 @01:31AM (#20512581)
Cilk does indeed sync on function return. You can also manually call 'cilk_sync'. I do think that Cilk’s approach is better (more in line with “make error states unrepresentable”, which I’m a big fan of), but Julia’s approach seems to be more in line with their overall goal of giving the programmer as much control as possible. Not sure if that’s a good thing or not, but as said above... we’ll find out soon!
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Re:Composable multi-threaded parallelism in Julia by gpderetta on Wednesday July 24, 2019 @07:22AM (#20514027)
Affine types to represent futures would help here.
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