Nagios Support Forum

Let's turn on some logging and see if this sheds any light on the issue.

Edit /usr/local/nagios/etc/pnp/process_perfdata.cfg
Set LOG_LEVEL = 2
Save file, change applies immediately.

Then watch the log file to see what it reports (it might take a minute for it to initially appear).
tail -f /usr/local/nagios/var/perfdata.log

Let us know if that has highlighted anything which could be causing the issue.

I don't understand what happened between then and now, but it appears the graphs started displaying performance data late Friday evening. The logs in Debug mode are displaying what I would think is expected results. So I suppose this is a rather fortunate (Graphs are working as intended), but unfortunate (Not sure what resolved the issue) circumstance.

It could be possible that you had an inordinate amount of performance data that was backed up, and your system finally got through the lot of it. We have definitely seen that in the past. Usually you can increase your load limits in NPCD, though not generally suggested as NPCD will take the maximum amount of resources you specify until it processes everything.