@Override
  public synchronized boolean removeInProgressReplica(DiskId diskId, ReplicaId replicaId){
    return removeReplicaFromMap(diskId, replicaId, true);
  }
The FCFSPrioritizationManager is a First-Come-First-Serve implementation of the PrioritizationManager.
ambry-prioritization/src/main/java/com/github/ambry/replica/prioritization/FCFSPrioritizationManager.java