When you grow, base typical settings is not enough. And you have error start zabbix-server
zbx_mem_realloc(): out of memory (requested x bytes)
zbx_mem_realloc(): please increase CacheSize configuration parameter
You hate to
vi /etc/zabbix/zabbix_server.conf
CacheSize=1024M
HistoryCacheSize=512M
TrendCacheSize=128M
#HistoryTextCacheSize=512M
ValueCacheSize=256M
StartPollers=20
StartIPMIPollers=10
HistoryCacheSize=512M
TrendCacheSize=128M
#HistoryTextCacheSize=512M
ValueCacheSize=256M
StartPollers=20
StartIPMIPollers=10
service zabbix-server restart
service zabbix-server status