Performance of the SNMP normalize function was improved.
Previously, each dynamic index was obtained individually when requested. On systems with thousands of dynamic indexes Zabbix pollers were 100% busy for more than 10 minutes until the cache was built up. Now the first dynamic index request will cause all indexes in the same SNMP table to be looked up and processed in one go. This greatly speeds up the cache building and reduces the SNMP query count. Note that all entries are looked up even if only some would be used later.
21.3 Miscellaneous improvements
Zabbix sender now supports ServerActive parameter from the agent daemon configuration file. The first IP address is used.