Sites are opened very slowly or the errors below occur:
Link to database can not be established: SQLSTATE [HY000]  Lost connection to MySQL server at 'waiting for initial communication packet', system error: 95 Link to database can not be established: SQLSTATE [HY000]  Too many connections
The number of connections permitted is controlled by the max_connections system variable. If you need to support more connections, you should set a larger value for this variable.
The current connections limit settings can be found using the following command:
# mysqladmin -uadmin -p`cat /etc/psa/.psa.shadow ` variables | grep 'max.*connections' | max_connections | 100 |
Increase it in configuration file of MySQL
[mysqld] set-variable=max_connections=150 set-variable=max_user_connections=20
Restart mysqld after to apply changings.
# /etc/init.d/mysqld restart
For more details check the MySQL reference manual "Too many connections"