3.3.4 CTM regulator
A CTM regulator is a process that solves a problem caused by request concentration on CTM daemons by regulating (consolidating) connections or requests. A CTM regulator is deployed at the front end of a CTM daemon, and distributes and consolidates connections or requests (invoke or remove requests) from EJB clients.
For example, in a large-scale system, if many clients issue many requests, the system might not operate stably or system-managed resources might become insufficient, preventing the system from operating normally. These phenomena are due to request concentration on CTM daemons that schedule requests. Request concentration increases the number of connections, causing processes to use a larger number of resources, such as opened files and sockets.
A CTM regulator is a special process that solves problems due to request concentration. CTM regulators consolidate connections from clients into one to control the number of connections established per CTM daemon. This control is called connection regulation. CTM regulators distribute resources to processes by regulating a large number of connections, so that a large-scale system can operate more stably.
The following figure shows how connections are regulated.
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![[Figure]](GRAPHICS/ZU030900.GIF)
When a CTM regulator receives a request from an EJB client, the CTM regulator transfers the request to the corresponding CTM daemon, and then waits for a reply. Upon receiving a reply, the CTM regulator returns the reply to the EJB client.
In CTM, multiple CTM regulators can be deployed per CTM daemon, as required. If a CTM regulator receives 256 or more requests simultaneously, performance might be degraded. In such a case, increase the number of CTM regulators, regardless of the number of client processes. Note that CTM regulators and the corresponding CTM daemon must be deployed on the same host.
For the integrated naming scheduler server model in which a naming service and a J2EE server are deployed on separate hosts, the integrated naming scheduler server does not accept any requests other than create. Therefore, CTM regulators do not need to be activated on the integrated naming scheduler server.