Why is not nginx_stats_sum updating?

Telegraf
1

Hi,

After 100-150 minutes of operation, nginx_stats_sum measurement is not updated.
It is good for other measurement.

Why is not nginx_stats_sum updating?

Telegraf configure 
[[inputs.nginx_vts]]
  urls = ["http://localhost/status"]

[[inputs.logparser]]
  files = ["/usr/service/logs/nginx/stats.log"]
  from_beginning = false

  [inputs.logparser.grok]
    measurement = "nginx_stats"
    patterns = ["%{TIMESTAMP_NGX} %{NEXT_FIELD}"]
    custom_patterns = '''
      TIMESTAMP_NGX %{YEAR}/%{MONTHNUM}/%{MONTHDAY} %{HOUR}:?%{MINUTE}(?::?%{SECOND})
      NEXT_FIELD \[%{LOGLEVEL}\] %{NUMBER}\#%{NUMBER}: pid:%{NUMBER:pid}\|from:%{NUMBER:from}\|to:%{NUMBER:to}\|accounting_id:%{DATA:accouting_id:tag}\|%{WORD:entry_type}:%{NUMBER:requests:int}\|bytes_in:%{NUMBER:in_bytes:int}\|bytes_out:%{NUMBER:out_bytes:int}\|latency_ms:%{NUMBER:latency_ms}\|upstream_latency_ms:%{NUMBER:upstream_latency_ms}\|%{GREEDYDATA:statuses}
    '''
[[processors.strings]]
  [[processors.strings.replace]]
    field = "statuses"
    old = ":"
    new = "="
[[processors.strings]]
  [[processors.strings.replace]]
    field = "statuses"
    old = "|"
    new = " "
[[processors.parser]]
  parse_fields = ["statuses"]
  data_format ="logfmt"
  merge = "override"

[[aggregators.basicstats]]
  name_override = "nginx_stats_sum"
  period = "30s"
  drop_original = false
  stats = ["sum"]

Thank you.

2

I do not know why, but …
I confirmed that it operates normally in Telegraf 1.9.1

Thank you.