Statics collector

Hi, I'm working in postgresSQL 9.3, I want to monitoring my server and I
try to use Statistics Collector, in the documentation said the parameters
that it need to configurate (only erease the #, isn't it?) and it see like:

# - Query/Index Statistics Collector -

track_activities = on
track_counts = on
track_io_timing = off
track_functions = all            # none, pl, all
track_activity_query_size = 1024    # (change requires restart)
update_process_title = on
stats_temp_directory = 'pg_stat_tmp'


# - Statistics Monitoring -

#log_parser_stats = off
#log_planner_stats = off
#log_executor_stats = off
#log_statement_stats = off

I want to see the information in pg_stat_tmp but it doesn't have anything.
What I need to configure? I hope you can help me..