UIM data_engine queue increased to the great extent with mysql database

Document ID : KB000123523
Last Modified Date : 23/12/2018
Show Technical Document Details
On the Primary hub the data_engine queue is getting backed up and not inserting data in the mysql database .
Also observe the below alarm message send by data_engine 

data_engine alarm
UIM 8.51
mysql database 5.6
The data_engine probe was configured for multithreading 
thread_count_insert = 4

Below errors observed in data_engine logs 
Line 1216: Dec 19 02:00:31:211 [139983885346560] de: QOS_ORACLE_RESOURCE_UTILIZATION_PERCENT [QoSData] - Open - Error: [QoSData] thread_id: 3874, error: Open: Too many connections (errno:1040) 
Line 1224: Dec 19 02:00:31:212 [139983885346560] de: QOS_ORACLE_TABLESPACE_FREE [QoSData] - Open - Error: [QoSData] thread_id: 3875, error: Open: Too many connections (errno:1040) 

 Login as the root user and run the following command in mysql database 

show global variables like '%max_connections%'; 

mysql> show global variables like '%max_connections%'; 
| Variable_name | Value | 
| max_connections | 214 | 
1 row in set (0.00 sec) 

To increase this value, log into the MySQL database using the root user and increase the max_connections variable to a higher value. 

SET GLOBAL max_connections = 1000; 

This method above does not require a server restart. Please note that after MySQL server restart, the max_connection variable value will again roll back to the previous value. 
In order to make the max_connections value persistent, modify the value in the configuration file my.cnf 

    Stop the MySQL server:
    Service mysql stop
    Edit the configuration file my.cnf
    vi /etc/my.cnf
    Find the variable max_connections under mysqld section.
    max_connections = 1000
    Set the higher value and save the file
    Start the server
    Service mysqld start

After the above setting was done observed the data_engine queue was processing correctly in the hub status gui 

Additional Information: