DBMS that supports this standard can function as a resource manager under the control
of a TP Monitor acting as a transaction manager. We discuss distributed transactions
and the DTP standard in Chapters 22 and 23.
• Load balancing The TP Monitor can balance client requests across multiple DBMSs
on one or more computers by directing client service calls to the least loaded server.
In addition, it can dynamically bring in additional DBMSs as required to provide the
necessary performance.
• Funneling In environments with a large number of users, it may sometimes be
difficult for all users to be logged on simultaneously to the DBMS. In many cases, we
would find that users generally do not need continuous access to the DBMS. Instead
of each user connecting to the DBMS, the TP Monitor can establish connections
with the DBMSs as and when required, and can funnel user requests through these
connections. This allows a larger number of users to access the available DBMSs with
a potentially much smaller number of connections, which in turn would mean less
resource usage.
• Increased reliability The TP Monitor acts as a transaction manager, performing the
necessary actions to maintain the consistency of the database, with the DBMS acting as
aresource manager. If the DBMS fails, the TP Monitor may be able to resubmit the
transaction to another DBMS or can hold the transaction until the DBMS becomes
available again.
TP Monitors are typically used in environments with a very high volume of transactions,
where the TP Monitor can be used to offload processes from the DBMS server. Prominent
examples of TP Monitors include CICS and Encina from IBM (which are primarily used
on IBM AIX or Windows NT and bundled now in the IBM TXSeries) and Tuxedo from
BEA Systems.
DBMS that supports this standard can function as a resource manager under the control
of a TP Monitor acting as a transaction manager. We discuss distributed transactions
and the DTP standard in Chapters 22 and 23.
• Load balancing The TP Monitor can balance client requests across multiple DBMSs
on one or more computers by directing client service calls to the least loaded server.
In addition, it can dynamically bring in additional DBMSs as required to provide the
necessary performance.
• Funneling In environments with a large number of users, it may sometimes be
difficult for all users to be logged on simultaneously to the DBMS. In many cases, we
would find that users generally do not need continuous access to the DBMS. Instead
of each user connecting to the DBMS, the TP Monitor can establish connections
with the DBMSs as and when required, and can funnel user requests through these
connections. This allows a larger number of users to access the available DBMSs with
a potentially much smaller number of connections, which in turn would mean less
resource usage.
• Increased reliability The TP Monitor acts as a transaction manager, performing the
necessary actions to maintain the consistency of the database, with the DBMS acting as
aresource manager. If the DBMS fails, the TP Monitor may be able to resubmit the
transaction to another DBMS or can hold the transaction until the DBMS becomes
available again.
TP Monitors are typically used in environments with a very high volume of transactions,
where the TP Monitor can be used to offload processes from the DBMS server. Prominent
examples of TP Monitors include CICS and Encina from IBM (which are primarily used
on IBM AIX or Windows NT and bundled now in the IBM TXSeries) and Tuxedo from
BEA Systems.
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