SQL/MX 2.x Installation and Management Guide (H06.10+, J06.03+)

Measuring Performance
HP NonStop SQL/MX Installation and Management Guide—544536-007
14-7
Statistics and Reports for NonStop SQL/MX
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Escalations of locks
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Deletes
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Disk reads
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Lock waits
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Message activity
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Reads
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Records accessed
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Records used
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Updates
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Writes
The FILE report can provide specific data on SQL tables. You can use the FILE report
along with other reports on a specific volume or subvolume.
NonStop SQL/MX does not collect statistics on timeouts or file-busy-time (the time
spent waiting on file I/O activities). In NonStop SQL/MX, there is no file I/O waiting as
there is for NonStop SQL/MP. The SQL/MX interface to the disk process is inherently
nowaited.
For queries that involve multiple SQL tables or compound statements, the statistics
data for the accessed tables might all be added to a single table, depending on
whether the operations are performed by the same Data Access Manager (DAM).
PROCESSH Statistics
SQLPROC and SQLSTMT are useful, but a process could be spending time in user
functions that do not contain SQL statements or in system code or system libraries. To
gather statistics on these, use PROCESSH.
The PROCESSH entity type provides information about the relative execution time of
one or more code ranges within a program. You can measure code ranges by
specifying procedure names and address ranges or by specifying a code-space
category (user code, user library, system code, or system library).
For H-series systems, PROCESSH provides information about all DLLs in system
libraries for DLLs that are named in the ADD PROCESSH statement. This information
includes the percentage of execution time occurring within each named library.
DISKFILE and DISCOPEN Statistics
The DISKFILE and DISCOPEN entities can be useful for database access and load
management. Both entities return ANSI SQL name information.
The DISKFILE entity gathers activity statistics against all partitions of a file object. Use
DISKFILE to determine if data is being evenly distributed across all the partitions in a
database.
You must use DISCOPEN to determine how data is distributed among all partitions of a
FILE. The DISCOPEN entity gathers statistics for partition opens by process. Use