Sun Microsystems Sun GlassFish Enterprise Server 2.1, Руководство администратора

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Editing a JDBC Connection Pool
The Edit JDBC Connection Pool page provides the means to change all of the settings for an
existing pool except its name.
1. Change general settings.
The values of the general settings depend on the specific JDBC driver that is installed. These
settings are the names of classes or interfaces in the Java programming language.
Parameter Description
DataSource Class Name The vendor-specific class name that implements the
DataSource
and / or
XADataSource
APIs. This class is in the JDBC driver.
Resource Type Choices include
javax.sql.DataSource
(local transactions only),
javax.sql.XADataSource
(global transactions), and
java.sql.ConnectionPoolDataSource
(local transactions, possible
performance improvements).
2. Change pool settings.
A set of physical database connections reside in the pool. When an application requests a
connection, the connection is removed from the pool, and when the application releases the
connection, it is returned to the pool.
Parameter Description
Initial and Minimum Pool Size The minimum number of connections in the pool. This value also
determines the number of connections placed in the pool when the pool is
first created.
Maximum Pool Size The maximum number of connections in the pool.
Pool Resize Quantity When the pool scales up and scales down towards the maximum and
minimum pool sizes respectively, it is resized in batches. This value
determines the number of connections in the batch. Making this value too
large delays connection creation and recycling; making it too small will be
less efficient.
Idle Timeout The maximum time in seconds that a connection can remain idle in the
pool. After this time expires, the connection is removed from the pool.
Max Wait Time The amount of time the application requesting a connection will wait before
getting a connection timeout. Because the default wait time is long, the
application might appear to hang indefinitely.
3. Change connection validation settings.
Working with JDBC Connection Pools
Sun GlassFish Enterprise Server 2.1 Administration Guide • December 2008 48