ODBC Server Installation and Management Manual

Managing the NonStop ODBC Server
HP NonStop ODBC Server Installation and Management Manual—429395-002
4-11
Using Stored Procedures
SQL statements. If a batch is to include several hundred (> 300) SQL statements, the
heap size for the NonStop ODBC Server process needs to be set higher than the
recommended default of 750 KB. As a rule, allocate 2.5 KB per SQL statement when
calculating the heap size.
Batches are not supported in ODBC.
Using Stored Procedures
Using a stored procedure, a client can submit a single execution request and have the
server execute a complex logic sequence that can include as many SQL statements as
needed. See Section 5, “Stored Procedures,” in the NonStop ODBC Server Reference
Manual for further details on how to use stored procedures with the NonStop ODBC
Server.
Managing Connect/Disconnect Processing
Even though the use of prelaunched servers provides good response time for
connection requests, it is still true that, in general, applications should try to minimize
the number of connect and disconnect requests that are used. It should be noted,
however, that each connection request results in a NonStop ODBC Server process and
a SQLCOMP process being assigned, so it is also true that you should not keep
connections open for extended periods.
If you experience long connect times, you should use SCF to check the number of
servers available for each of the server classes and adjust the numbers as necessary.
See Configuring and Managing SCS on page 4-1, and Using the Subsystem Control
Facility on page 4-29, for further information.
Configuring Communication Stacks
When configuring the communication stacks on the client, you must take care to
ensure that the various configuration parameters have been set to optimize
performance. For example, for some stacks there is a configuration parameter that
specifies how long to wait on disconnection requests before returning to the client. If
this parameter is set to a high value, it will affect the time taken for a client to
disconnect from the server. This particular problem can be easily checked by seeing
how long a disconnection takes by using either the NonStop ODBC Server
Connectivity Tool under Windows or ISQL in a different environment.
Complete information related to installation of the communication stacks can be
obtained from the vendor of the communication stack being used.
Setting Up SCS
For the best performance, it is recommended that the SCS process run in a different
CPU from the NonStop ODBC Server processes and the TCP/IP process. If it is
running in a separate CPU, the priority of the SCS process should be as high as