ODBC Server Installation and Management Manual

Managing the NonStop ODBC Server
HP NonStop ODBC Server Installation and Management Manual—429395-002
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Configuring SQL/MP
possible. If SCS is running in the same CPU as NonStop ODBC Server processes, the
priority of SCS should be lower than that of the NonStop ODBC Server processes.
Configuring SQL/MP
Set up the NonStop SQL/MP system to provide optimum performance. Ensure that the
DP2 cache is configured correctly for the volumes where the NonStop ODBC Server
catalogs reside, for example, and provide a general tuning of the database for optimal
query performance.
To ensure the best performance from the NonStop ODBC Server, keep the SQL
statistics current on the NonStop ODBC Server catalog tables COLUMNS, INDEXES,
TABLES, ZNUIX, and ZNUOBJ. This strategy is particularly necessary for any NonStop
ODBC Server databases in which there has been a lot of activity involving adding and
dropping tables. A good indication of a problem in this area is if a NOSUTIL REFRESH
operation takes a long time to finish.
A sample SQLCI command to update the statistics follows:
UPDATE ALL STATISTICS FOR TABLE ZNUOBJ NORECOMPILE;
Using the NonStop ODBC Server Connectivity Tool
In the Windows environment, you should use the Connectivity Tool for measuring
performance and locating performance problems. Options provided by the Connectivity
Tool follow:
For the preceding options, you should generally request at least five samples, then
display the resulting graph to look for unexpected variances. For example, the graph is
very useful for showing the effects of statement caching, where the first statement
execution time should be much longer than subsequent executions.
CONNECT Use this option to determine the amount of time it takes to connect to a
NonStop ODBC Server for a given user ID and in conjunction with the
SCF STATUS commands to check that the correct server class is
being used for a given user.
ECHO Use this option to send a pass-through statement to a NonStop ODBC
Server; the only action the Server takes is to reply immediately. This
option provides a measurement for the minimum amount of time it
takes for an NonStop ODBC Server to process a request: the request
latency time. In general, a long response time indicates either a LAN
problem or a problem with the CPU in which the NonStop ODBC
Server, or SCS, or network IOPs are running.
QUERY Use this option to determine how long it takes to execute a SQL query.
For a SELECT statement, the time is the amount of time for the first
result packet to reach the Connectivity Tool.