Currently the ocaml runtime has a global lock on running ocaml. Like python you may have multiple OS threads but only one may have this lock at a time. Non-ocam

Currently the ocaml runtime has a global lock on running ocaml. Like python you may have multiple OS threads but only one may have this lock at a time. Non-ocaml code may release this lock while e.g. doing blocking IO. The goal is to remove this lock in a way that is safe and allows programs to continue being fast.