Added a couple of comments [skip CI]
Added a couple of comments [skip CI]


Former-commit-id: ad3d55992df65fa21fae62f8c21f6be4d8925589 [formerly 7665c563bd06f9259ebedff64580854b95112bd0]
Former-commit-id: 9e1855ef9b81778183adbb8a19901704e1284679
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine