GWT SDM hanging on recompiles?

Greetings everyone.

Hopefully someone can tell me what I need to change.

When running SDM via Gradle, after so many recompiles, it will stop with something similar to:

 GET /recompile/gwt
   Job com.newsrx.ButterAdmin_1_7
      starting job: com.newsrx.ButterAdmin_1_7

and never actually do the compile.

A non-hung recompile looks like:

GET /recompile/gwt
   Job com.newsrx.ButterAdmin_1_6
      starting job: com.newsrx.ButterAdmin_1_6
      binding: locale=default
      binding: user.agent=safari
      Compiling module com.newsrx.ButterAdmin
         Unification traversed 876 fields and methods and 394 types. 17 are considered part of the current module and 26 had all of their fields and methods traversed.
         Compiling 1 permutation
            Compiling permutation 0...
            Linking per-type JS with 17 new/changed types.
            Source Maps Enabled
         Compile of permutations succeeded
         Compilation succeeded -- 2.086s
      Linking into /home/michael/git/ButterAdmin/ButterAdmin-client/build/gwt/work/com.newsrx.ButterAdmin/compile-8/war/gwt; Writing extras to /home/michael/git/ButterAdmin/ButterAdmin-client/build/gwt/work/com.newsrx.ButterAdmin/compile-8/extras/gwt
         Link succeeded
         Linking succeeded -- 0.186s
      2.475s total -- Compile completed


To fix the issue I have to kill it and start it over.

Pointers as to what might be causing this?

AdoptOpenJDK11 -> with -release 8.