Repetitive power cycle test (over 10 minutes) , where the mongod host is power cycled (non-clean shutdown) randomly (every 30 to 120 seconds) , while clients are sending various CRUD operations. The operations which produce a mongod crashes of Invariant failure false src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.cpp 179 and Invariant failure false src/mongo/db/storage/mmap_v1/btree/btree_logic.cpp 395 db.foo.validate() bulk.insert() db.foo.remove() Use the attached powertest.sh, which relies on FSM & CRUD clients to generate various DB operations to reproduce the issue (in 3.1.6). ./powertest.sh -s <ssh server> -e mmapv1 -F $HOME/mongo <ssh server> ssh server connection, i.e., "-i ident.pem user@host"