SQL/MX 3.1 Installation and Management Guide (H06.23+, J06.12+)

Measuring Performance
HP NonStop SQL/MX Release 3.1 Installation and Management Guide—663852-001
14-6
Measure Performance Measurement Tool
You can collect performance statistics for SQL/MX objects by using these Measure
entities:

SQLPROC provides information about an SQL process. There is one SQLPROC
counter record per SQL process selected.

SQLSTMT provides information about all SQL statements within an SQL process.
There is one SQLSTMT counter record per SQL statement of a selected SQL
process.

FILE enables an SQL database object to be selected to accumulate information
about file activities.
Figure 14-1
illustrates Measure entities and corresponding program structures for SQL
processes.
To reduce the cost of overhead for the Measure interface to NonStop SQL/MX, the
Measure product updates more than one counter per call. The overall cost of using the
Measure product depends on the frequency of the intervals for measurements and on
the number of active SQL statements. As the number of active SQL statements in a
program increases, the cost of performing measurements increases.
The Measure product provides other entities to measure activity on processes,
processors, and disk processes. For information on how to set up the Measure product
Note. A SQLSTMT record is created when at the beginning of the processing of a SQL
statement, SQL invokes a Measure interface to check if SQL statements are required. If the
SQL statements are required, SQL invokes the API to set up the measure records. This means
that SQLSTMTs of processes that are already active when a measurement is started might not
get reported.
Figure 14-1. Measure Entities and Program Structures
Procedure 1
SQL Statement 1
SQL Statement 2
SQL Statement 3
Access T1, T2,T3
Procedure 2
SQL Statement 1
SQL Statement 2
SQL Statement 3
Access T1, T2,T3
SQLSTMT
SQLSTMT
SQLSTMT
SQLSTMT
SQLSTMT
SQLSTMT
SQLPROC
Process (Program)
Measure Entities
FILE
FILE
FILE
Tables
•••
VST009.vsd
T3
T2
T1