I faced with a problem. Zabbix server wont start due to a memory error. logs details are below:

12602:20170625:172324.743 __mem_malloc: skipped 4 asked 29472 skip_min 448 skip_max 3032
12602:20170625:172324.744 file:dbconfig.c,line:446 zbx_mem_realloc(): out of memory (requested 29472 bytes)
12602:20170625:172324.744 file:dbconfig.c,line:446 zbx_mem_realloc(): please increase CacheSize configuration parameter
12595:20170625:172324.746 One child process died (PID:12602,exitcode/signal:1). Exiting ...

I already tried increasing CacheSize(4096M), TrendCacheSize, HistoryCacheSize (1024M or 2048M)and the server Memory(up to 8GB), and its still not working.

The number of hosts is 211(146 running),
The number of items is 13800(13645 is running),
The number of triggers is 3625(3447 is ok),
When I enable 1 hosts, the service will not wok, search for many case's solution, but have no effect.

I would appreciate it that you give me some suggestions.
Many thanks.