Added warning on slow splitting [skip hazardlib]
Added warning on slow splitting [skip hazardlib]


Former-commit-id: 5579021a4cb2dd9f72e217bc440dbeea2daa643b [formerly f2695f5d587b1ea342020d7562ae55512cdf9b71]
Former-commit-id: 4f01d682975ace0b39f44f9dc80828a491e8b45a
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine