# Buggy code
def __init__(self):
    self.entries = {}
    self.errors = {}
    self.total = StatsEntry(self, "Aggregated", None, use_response_times_cache=True)


# Traceback (ValueError)
[2020-04-06 13:01:45,700] Jonatans-Air.localdomain/ERROR/stderr: Traceback (most recent call last):
[2020-04-06 13:01:45,700] Jonatans-Air.localdomain/ERROR/stderr: File "/Users/heyman/virtualenvs/locust/bin/locust", line 11, in <module>
[2020-04-06 13:01:45,702] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,702] Jonatans-Air.localdomain/ERROR/stderr: load_entry_point('locustio', 'console_scripts', 'locust')()
[2020-04-06 13:01:45,702] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,702] Jonatans-Air.localdomain/ERROR/stderr: File "/Users/heyman/projects/locust/locust/main.py", line 297, in main
[2020-04-06 13:01:45,703] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,703] Jonatans-Air.localdomain/ERROR/stderr: shutdown(code=code)
[2020-04-06 13:01:45,703] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,704] Jonatans-Air.localdomain/ERROR/stderr: File "/Users/heyman/projects/locust/locust/main.py", line 281, in shutdown
[2020-04-06 13:01:45,705] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,705] Jonatans-Air.localdomain/ERROR/stderr: write_stat_csvs(runner.stats, options.csvfilebase, options.stats_history_enabled)
[2020-04-06 13:01:45,705] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,706] Jonatans-Air.localdomain/ERROR/stderr: File "/Users/heyman/projects/locust/locust/stats.py", line 757, in write_stat_csvs
[2020-04-06 13:01:45,706] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,706] Jonatans-Air.localdomain/ERROR/stderr: f.write(stats_history_csv(stats, stats_history_enabled) + "\n")
[2020-04-06 13:01:45,707] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,707] Jonatans-Air.localdomain/ERROR/stderr: File "/Users/heyman/projects/locust/locust/stats.py", line 871, in stats_history_csv
[2020-04-06 13:01:45,708] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,708] Jonatans-Air.localdomain/ERROR/stderr: percentile_str = ','.join([
[2020-04-06 13:01:45,708] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,708] Jonatans-Air.localdomain/ERROR/stderr: File "/Users/heyman/projects/locust/locust/stats.py", line 872, in <listcomp>
[2020-04-06 13:01:45,709] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,710] Jonatans-Air.localdomain/ERROR/stderr: str(int(s.get_current_response_time_percentile(x) or 0)) for x in PERCENTILES_TO_REPORT])
[2020-04-06 13:01:45,710] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,710] Jonatans-Air.localdomain/ERROR/stderr: File "/Users/heyman/projects/locust/locust/stats.py", line 508, in get_current_response_time_percentile
[2020-04-06 13:01:45,711] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,711] Jonatans-Air.localdomain/ERROR/stderr: raise ValueError("StatsEntry.use_response_times_cache must be set to True if we should be able to calculate the _current_ response time percentile")
[2020-04-06 13:01:45,711] Jonatans-Air.localdomain/ERROR/stderr:
[2020-04-06 13:01:45,711] Jonatans-Air.localdomain/ERROR/stderr: ValueError
[2020-04-06 13:01:45,711] Jonatans-Air.localdomain/ERROR/stderr: :
[2020-04-06 13:01:45,711] Jonatans-Air.localdomain/ERROR/stderr: StatsEntry.use_response_times_cache must be set to True if we should be able to calculate the _current_ response time percentile
[2020-04-06 13:01:45,711] Jonatans-Air.localdomain/ERROR/stderr:

# Fixed code
def __init__(self, use_response_times_cache=True):
    """
    The value of use_response_times_cache will be set for each StatsEntry() when they are created.
    Settings it to False saves some memory and CPU cycles which we can do on worker nodes where
    the response_times_cache is not needed.
    """
    self.use_response_times_cache = use_response_times_cache
    self.entries = {}
    self.errors = {}
    self.total = StatsEntry(
        self, "Aggregated", None, use_response_times_cache=self.use_response_times_cache
    )