When a replica set node persists the last response to replSetRequestVotes to the local.replset.election, it currently acquires the PBWM lock as part of the collection lock acquisition. This is unnecessary and could affect availability when the node is having issues during oplog application.

The node can opt out of acquiring the PBWM lock using the ShouldNotConflictWithSecondaryBatchApplicationBlock.

This issue was previously raised (see comment) as part of SERVER-48398.