Collectd rrdcached plugin failure update same time

Hi,

does anyone know the cause of rrdcached failure message:

Dec 12 17:40:48 omv4 collectd[3075]: rrdcached plugin: rrdc_update (/var/lib/rrdcached/db/localhost/df-root/df_complex-free.rrd, [1576168848:2709159936.000000], 1) failed: rrdcached: illegal attempt to update using time 1576168848.000000 when last update time is 1576168848.000000 (minimum one second step) (status=-1)

I can`t find informations referring this, because the times are the same...

regards

Hi

results from omv-firstaid:

Checking all RRD files. Please wait ...
All RRD database files are valid.

My time settings:

root@omv4:~# timedatectl
Local time: Mi 2019-12-18 18:03:08 CET
Universal time: Mi 2019-12-18 17:03:08 UTC
RTC time: Mi 2019-12-18 17:03:07
Time zone: Europe/Berlin (CET, +0100)
Network time on: yes
NTP synchronized: yes
RTC in local TZ: no

Is there anything wrong?