A memory controller may include a buffer memory configured to store a plurality of metadata groups and a journal log set for a metadata group of the plurality of metadata groups, wherein the journal log set includes a plurality of journal logs respectively indicating update information for the plurality of metadata groups. The memory controller may include control circuitry configured to identify journal times taken to execute respective journal logs of the plurality of journal logs, identify a prediction time taken to update the metadata group based on the journal log set, and control a number of journal logs included in the journal log set based on the journal times and the prediction time.