Appendix B. Monitoring CM databases with Performance Expert 491
recommendations that are described in “Monitoring the health of the CM DB2
databases” on page 480 to determine how your system could be improved.
Figure B-7 shows the display of an exception on the System Overview panel and
a drill down into one exception.
Figure B-7 List of exceptions and exception details
Monitoring the connections and agents of your CM library server
Monitoring your connections and agents on the CM Library Server machine has
two aspects:
Determine whether you should turn on the DB2 connection concentrator and
whether connection pooling configurations are optimal
Determine whether your agent, application, and connection settings are
correct in the database and database manager configuration
492 DB2 Performance Expert for Multiplatforms V2.2
Determining the need of using the DB2 connection
concentrator
Figure B-8 depicts two different CM Library Server environments.
In one environment, a “fat” client is used to connect to the CM Library Server
machine. This client does not have the ability to do connection pooling. If
many users are using a “fat” client, then as many connections are kept to the
CM Library Server database, which are idle very often. With each connection,
a db2fmp process and an agent is associated, which consumes system
resources all the time. In this environment, connection pooling on the DB2
side might be useful if too many system resources are allocated.
In the other environment, a mid-tier server is used between the CM Library
Server machine and a group of Web applications that are using eClients. The
mid-tier server has the ability to do connection pooling, which must explicitly
be configured. This is the recommended approach, because it saves
resources on the CM Library Server. Depending on the connection pooling
configuration, only a few connections are kept to the CM Library Server
database, which are shared among all the Web applications. In an ideal
connection pooling configuration, connections are busy most of the time.
Figure B-8 CM connection pooling environments
ICM Connector
JDBC
DB2 connection
db2fmp
CM stored procedure
DB2 agent
Client program
DB2 database tables
DB2 agent
Library Server
machine
“fat” client
machine
ICM Connector
JDBC
DB2 connection
db2fmp
CM stored procedure
DB2 agent
Web application
Mid-tier server
db2fmp
connection often idle mid-tier pool keeps connection busy
DB2 Connection Concentrator
Appendix B. Monitoring CM databases with Performance Expert 493
You can use Performance Expert to monitor both types environments and to
detect whether a connection concentrator should be used for the “fat” client
connections or whether the connection pooling configuration on the mid-tier
server is optimal.
In Performance Expert, select Statistics Details Databases. Select the CM
Library Server database and double-click it. The Application window is
displayed (Figure B-9), which contains useful information about the number of
connections and agents in your Library Server database.
Figure B-9 Connection information shown in PE with connection concentrator
The Application pane shows that 421 applications are currently connected to the
CM Library Server database (Applications connected to DB). The high water
mark of connections since the database was activated is 421 connections (Max.
concurrent connections).
The connection high water mark determines the value that you should use for the
MAX_APPLS parameter in the database configuration of the CM Library Server
database. If the MAX_APPLS value is currently set to a lower value, increase it. If
it is set to a higher value, consider decreasing it. But before doing so, monitor the
connection high water mark value for several days or weeks to determine the
correct value.

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