862915 - Support PJS operations in workers

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, defect)

Description

[Niko Matsakis [:nmatsakis]]

Currently, workers do not have access to PJS operations.  Or rather, they can use the API, but they will not get parallel execution.  This is because we have one threadpool per runtime and the result would be far too many threads (N cores * M workers).  

To improve the situation, I would like to separate out the threadpool so that it can be shared between runtimes.  We would then allow all webworkers to share the same threadpool.  Likely they would still use a different threadpool from the main thread: this would guarantee that the main thread never blocks on a worker (though workers may block on one another if the threadpool is in use---note that no deadlocks would be possible).