Improve stability of num_workers config test (#4093)
Improve stability of num_workers config test (#4093)


jakirkham/dask,ContinuumIO/dask,mrocklin/dask,blaze/dask,jcrist/dask,blaze/dask,jcrist/dask,dask/dask,mrocklin/dask,jakirkham/dask,ContinuumIO/dask,dask/dask