Steps to reproduce:

1. No steps known to reproduce

Result:

Every hour a peak in Poller Data Collector processes is shown. See screenshot.

Have the same issue at another customer, also every hour but at a different time.

Log files don't show why there is a queue, queue details show multiple devices, multiple items (not specific items, just general SNMP devices (interfaces etc) or zabbix-agent items (Linux by Zabbix agent template)).

No custom intervals are set, all type: Flexible.

Setting the StartPollers parameter higher eases the pain, but still a peak every hour.

Expected:
More spread item polling