wproc Core Worker issues on Nagios Core 4.4.5

[stanfordlone]

Nagios Core 4.4.5.

I've been seeing a lot of these log entries in nagios.log:
[1599268709] wproc: Core Worker 11835: tv.tv_sec is currently 1599268704
[1599268709] wproc: Core Worker 11835: Failed to reap child with pid 17369. Next attempt @ 1599268709.8463
[1599268709] wproc: Core Worker 11835: kill(-17369, SIGKILL) failed: Operation not permitted
[1599268709] wproc: Core Worker 11835: job 574 (pid=17369): Dormant child reaped

They usually occur in bunches. Sometimes the nagios.log isn't written to for over 60 secs. Other times, it appears that all service and host checks fail to run (status.dat is not updated), but the nagios service and UI are fine. In this case a nagios service restart fixes the problem.

But I'd like to know what's causing this and more importantly, is there anything that can be done to prevent these issues from happening. Just curious if anyone else is experiencing this issue and if there is a solution to fix it.