Is automatic yield support feasible for threads?

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AFAIK Emacs has cooperative threading, so a badly behaving thread can prevent UI updates, therefore if some costly operation is moved into a separate thread then the code has to be modified in order to yield periodically if the code doesn't do I/O.

If that's the case then what if the interpreter itself could support automatic yielding when some flag is set, so it could yield automatically after every several instructions?

For example, make-thread could have an optional argument specifying after how many instructions a thread-yield should be called automatically and if this argument is set then a global flag is set, so the interpreter knowns it should call yield regularly.

This automatic yielding would have some cost, but in return any code could safely be moved into a separate thread without the danger of locking up the UI if this optional argument is given to make-thread. So it could makes using cooperative threads easier.

Could such an automatic yield support be feasible for threads?