Chapter 28 Using Connection Management

When to use Connection Manager

Components that use Jaguar transactions must use cached connections to interact with remote databases. Otherwise, work done on the connection is not affected by the outcome of the transaction.

Components that use cached connections can realize improved performance and scalability for the following reasons:

Improved performance - Connection Manager allows client sessions to share previously opened third-tier connections so that server CPU time and memory are not consumed by opening more connections than necessary.
Improved scalability - since connection caching allows the same number of clients to be serviced using fewer third-tier connections, less memory and other resources are required to maintain third-tier connections.

To realize these benefits, a component must be coded to use a cached connection only when necessary and to release the connection back to the cache at other times. Do not let your components hold connections while waiting for more input from the client application. As a general rule, each method call that requires a third-tier connection should take a connection handle when invoked and release it before returning.