docs: @Nonnull
  	@Override
  	public RunnableFuture<SnapshotResult<OperatorStateHandle>> snapshot(
  		long checkpointId,
  		long timestamp,
  		@Nonnull CheckpointStreamFactory streamFactory,
  		@Nonnull CheckpointOptions checkpointOptions) throws Exception {
  
  		long syncStartTime = System.currentTimeMillis();
  
  		RunnableFuture<SnapshotResult<OperatorStateHandle>> snapshotRunner =
  			snapshotStrategy.snapshot(checkpointId, timestamp, streamFactory, checkpointOptions);
  
  		snapshotStrategy.logSyncCompleted(streamFactory, syncStartTime);
  		return snapshotRunner;
  	}