max_coordagents - Maximum number of coordinating agents configuration parameter
You can use this parameter to limit the number of coordinating agents.
- Configuration type
- Database manager
- Applies to
- Database server with local and remote clients
- Database server with local clients
- Partitioned database server with local and remote clients
- Parameter type
- Configurable online
- Default [range]
- 200, AUTOMATIC [-1, 1 - 64
A setting of -1 translates into a value of 200.
For details on the restrictions and the behavior of interactions of max_connections and max_coordagents in a concentrator environment (including AUTOMATIC settings), see: Restrictions and behavior when configuring max_coordagents and max_connections.
When the Concentrator is OFF, that is, when max_connections is equal to or less than max_coordagents, this parameter determines the maximum number of coordinating agents that can exist at one time on a server node.
One coordinating agent is acquired for each local or remote application that connects to a database or attaches to an instance. Requests that require an instance attachment include CREATE DATABASE, DROP DATABASE, and Database System Monitor commands.
When the Concentrator is ON, that is, when max_connections is greater than max_coordagents, there might be more connections than coordinator agents to service them. An application is in an active state only if there is a coordinator agent servicing it. Otherwise, the application is in an inactive state. Requests from an active application are serviced by the database coordinator agent and subagents in SMP or MPP configurations. Requests from an inactive application are queued until a database coordinator agent is assigned to service the application, when the application becomes active. As a result, this parameter might be used to control the load on the system.
- Administrative tasks
- Capturing snapshot information
- Critical troubleshooting tasks
- Maintenance tasks, such as forcing users off the system