Database Visibility provides metrics on the performance of your database and helps troubleshoot performance related issues.
Components of Database Visibility
AppDynamics Database Visibility consists of four main components:
- Database Agent
- Events Service (on-premises only)
The AppDynamics Database Agent is a standalone Java program that collects performance metrics about your database instances and database servers.
You can deploy the Database Agent on any machine running Java 1.7 or higher. The machine must have network access to the AppDynamics Controller and the database instance that you want to be monitored.
A database agent running on a typical machine with 16 GB of memory can monitor about 25 database instances. On larger machines, a database agent can monitor up to 200 database instances. To monitor more than 100 database instances, increase the initially allocated heap size for the Database Agent JVM. See Database Visibility Supported Environments
The Database Agent Collector is the process that runs within the Database Agent to collect performance metrics about your database instances and database servers. One Collector collects metrics for one database instance. Multiple collectors can run in one Database Agent.
AppDynamics Database Visibility detects when a database back end has matching credentials with a database server being monitored by a Collector. Database Visibility automatically associates the back end with the collector, so you can view its performance with the Application Flow Map, Tier Flow Map, or Node Flow Map.
The Controller is the central interface where you can see all your database instance and database server performance metrics.
The following types of information are sent to the Controller:
- Database-level metrics, such as number of queries processed and other database statistics
- Names and attributes of all sessions, clients, queries, and other objects on the monitored system
Event service stores high volumes of metric data. If you are using the on-premises version of Database Visibility, you must install the Events Service.
The following types of information are sent to the Events Service:
- time that each query spends at each wait state
- individual query statistics for databases that support it
- information about individual execution plans in databases that support it