Configuring Parameters for Pooling Default Connections
The following information describes how to enable or disable pooling
for default database connections using the parameters MaxSharedDbConns (DB Multiplex - Max Number of Shared DB Connections) and MinSharedDbConns (DB Multiplex - Min
Number of Shared DB Connections).
To enable connection pooling, set
MaxSharedDbConnsandMinSharedDbConnsto positive integer values (at least 1) that are no higher thanMaxTasksminus 1. A connection will be shared by more than one user session once the number of sessions within the multithreaded process exceeds the maximum number of shared connections allowed per process.MaxSharedDbConnscontrols the maximum number of pooled database connections for each multithreaded process.MinSharedDbConnscontrols the minimum number of pooled database connections that the Siebel Application Object Manager tries to keep available for each multithreaded process.The setting of
MinSharedDbConnsmust be equal to or less than the setting ofMaxSharedDbConns. Depending on your Siebel Application Object Manager usage patterns, set these to the same value or setMinSharedDbConnsto a lower value (if you determine this to be helpful in conserving database connection resources).
To configure persistent and shared database connection pooling, set
MaxSharedDbConns, using the appropriate ratio ofMaxTasksdivided byMaxSharedDbConns. Depending on the ratio, a greater or lesser degree of sharing will be in effect. Start with a 2:1 (or smaller) ratio forMaxTasksdivided byMaxSharedDbConns. With this example ratio, two user tasks will share the same database connection.To configure persistent but nonshared database connection pooling, set
MaxSharedDbConns=MaxTasksminus 1.To disable connection pooling, set
MaxSharedDbConnsandMinSharedDbConnsto -1 (this is the default value).
MaxSharedDbConns and MinSharedDbConns are defined per Siebel Application Object Manager component, on
an enterprise basis (these parameters are included in named subsystems
of type InfraDatasources). The database connections these parameters
control are not shared across multithreaded processes. The actual
maximum number of database connections for each multithreaded process
is determined by the ratio MaxSharedDbConns divided
by MaxMTServers.
MaxSharedDbConns and MinSharedDbConns work differently than MinTrxDbConns, which specifies
the number of shared specialized database connections available for
each multithreaded process. For details, see Configuring Pooling for Specialized Database Connections.