Growing queue after upgrading from 3.4 to 4

[Fooller]

Hello.
After upgrade from zabbix version 3.4 to 4.0 something went wrong with zabbix_server and zabbix_proxy: zabbix queue start growing. All queued items are located behind zabbix_proxy. If switch host monitoring to not using proxy - items are going off from queue.
There are 3 zabbix_proxy with not many host behind them. All performance/gathering/internal graphs are seems to be ok. On zabbix_server all graphs except "server performance" looks good.

Any suggestions are welcome.

Versions:
zabbix_server - 4.0.3
zabbix_proxy - 4.0.3
zabbix_agent - from 2.0 to 4.0

Info from zabbix system information:
Required server performance, new values per second: 50.47
Number of hosts: 34
Number of items: 3720

[ingus.vilnis]

Hello and welcome to Zabbix forums!

What type of items are queued and what are they monitoring? Are they not Zabbix agent (active) on Windows?

[Fooller]

Hello and welcome to Zabbix forums!

What type of items are queued and what are they monitoring? Are they not Zabbix agent (active) on Windows?

I'm using:
- Zabbix agent items in most cases (passive checks);
- SNMPv2 agent checks;
- Zabbix agent (active) - used only on FreeBSD and Linux systems;
- few web checks.

In queue I see all types of items.

[Andrzej PAwlik]

Try look time on zabbix_server, zabbix_proxy and host where is agent zabbix. (ntp for linux)

[dimir]

Since 4.0 Zabbix server does not adjust value timestamps when receiving data from proxy/active agent/sender anymore. So you must take care of time synchronization on all your machines now, best, using NTP as Andrzej PAwlik suggests.

[Fooller]

Try look time on zabbix_server, zabbix_proxy and host where is agent zabbix. (ntp for linux)

Since 4.0 Zabbix server does not adjust value timestamps when receiving data from proxy/active agent/sender anymore. So you must take care of time synchronization on all your machines now, best, using NTP as Andrzej PAwlik suggests.

Tnx, problem solved after synchronization time between zabbix_server and zabbix_proxy.