Why am I getting “Insufficient memory to allocate

Question

I have set up asterisk server with mysql. I am done with odbc and odbcinst.ini settings. But I am getting following error. 1) How to fix it?

[Jul 18 02:48:07] WARNING[23751]: res_config_mysql.c:1538 mysql_reconnect: MySQL RealTime: Insufficient memory to allocate MySQL resource.
[Jul 18 02:48:07] WARNING[23751]: res_config_mysql.c:1538 mysql_reconnect: MySQL RealTime: Insufficient memory to allocate MySQL resource.
[Jul 18 02:48:07] WARNING[23751]: res_config_mysql.c:1538 mysql_reconnect: MySQL RealTime: Insufficient memory to allocate MySQL resource.

2) After getting the above warning messages for some time, I get

Disconnected from Asterisk server
Asterisk cleanly ending (0).
Executing last minute cleanups

How to fix that too?