Tanzu - How to monitor number of connections to the CF database
Article ID: 431726
Updated On:
Products
Issue/Introduction
This KB article describes how to monitor number of connections to the CF database to ensure it does reach database limit.
As mentioned in TAS 10.2 Release Notes there is a database limit -
- DB Connections - Be careful this does not exceed any Database limit, and note that there are other connections to the CF Database, such as CC workers, Tanzu UAA, Diego etc.
It's important to make sure environment is staying under limit to avoid connection drops.
Resolution
Thee are Tanzu KPI metrics that report the max and used connections to internal MySQL Database. See KPI documentation.
The metrics of interest are;
- /mysql/variables/max_connections
- /p.mysql/net/max_used_connections
Recommended measurement max_used_connections / max_connections
Recommended alert thresholds Yellow warning: > 80 % Red critical: > 90 %
For max DB connections, you can also query this value from databse. directly by connecting to TAS database:
Example:
mysql> use ccdb;
Database changed
mysql> SHOW VARIABLES LIKE "max_connections";
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| max_connections | 3500 |
The number of max connections is tunable in Internal MySQL of Elastic Application Runtime tile.
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