JDBC Type 4 Driver 3.0 Programmer's Reference (SQL/MX 3.x)

Configuring MFC
For information on configuring MFC, see the HP NonStop SQL/MX Connectivity Service Manual.
Enabling MFC
The following property is required to use MFC in an application that uses the JDBC Type 4 driver:
enableMFC
To enable MFC, the value of this property must be set to ON. For example: -Dt4sqlmx.enableMFC
= ON.
In the JDBC Type 4 driver, MFC is enabled by default.
MFC Usage Scenarios
The benefits of lower processor and memory utilization mentioned below are applicable on the NonStop
Server.
JDBC T4 applications using java.sql.Connection.prepareStatement() have the
benefit of lower processor utilization, lower memory consumption, and better response time.
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JDBC T4 applications using complex queries through prepare calls, have higher benefit of lower
processor utilization, lower memory consumption, and better response time. For example,
Hibernate generated queries.
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JDBC T4 applications with higher driver side cache size can benefit from lower memory
utilization by using the combination of MFC and driver side MFU cache.
For example, an application with t4sqlmx.maxStatements=1000 can benefit by changing
to t4sqlmx.maxStatements=600 and MFC.
In this example, all statements are cached in MFC and the most frequently used statements are
cached in the driver side MFU cache.
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JDBC T4 applications, which have large number of statements that are SQL compiled at the
startup, can benefit from reduced (re-) startup time by using the MFC feature. In situations, where
servers are configured for automatic restart, the startup time is reduced.
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JDBC T4 applications experiencing high memory swapping can benefit from reducing the driver
side cache and enabling MFC. Reduce the driver side cache and enable MFC in the scenarios,
where the MXOSRVR process exceeds 1 GB in size frequently.
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For JDBC T4 applications where the large number of MXOSRVR processes is configured per
processor, enable MFC to reduce swapping. The other option is to increase the physical memory
per processor to reduce swapping.
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