Primary became unresponsive after consuming all swap (8gb). First replica auto became primary. Added more memory on the original primary and on try to start mongod, getting following in log-
2019-11-14T12:05:44.199-0500 I STORAGE [initandlisten] Taking 991 samples and assuming that each section of oplog contains approximately 16959969 records totaling to 15384507881 bytes
2019-11-14T12:07:10.996-0500 I CONTROL [signalProcessingThread] got signal 15 (Terminated), will terminate after current cmd ends
2019-11-14T12:07:10.996-0500 I NETWORK [signalProcessingThread] shutdown: going to close listening sockets…
2019-11-14T12:07:10.996-0500 I NETWORK [signalProcessingThread] removing socket file: /tmp/mongodb-27017.sock
2019-11-14T12:07:10.996-0500 I CONTROL [signalProcessingThread] now exiting
2019-11-14T12:07:10.996-0500 I CONTROL [signalProcessingThread] shutting down with code:0
New to mongo. How to figure this out?