IO Data Program Screen [ ALLBASE/SQL Performance and Monitoring Guidelines ] MPE/iX 5.0 Documentation
ALLBASE/SQL Performance and Monitoring Guidelines
IO Data Program Screen
This screen provides I/O data buffer pool information for each program
being run by sessions attached to the DBEnvironment.
To invoke the IO Data Program screen, use the d p command from the IO
subsystem or the /i d p command from other subsystems.
When you invoke this screen, its counters are set to zero.
Field Definitions
REFRESH The screen refresh rate, in seconds.
SESSIONS The number of DBEnvironment sessions.
SORTIODATA An indicator of how the programs are sorted. The
programs are sorted in descending order by the value in
the column marked with the asterisk. In the example
above, the programs are sorted by the DATA DISK WR
values. For more information, see the SET SORTIODATA
command.
CID The DBEnvironment connection identification number.
BUFF ACCESS The number of page requests the session has issued to
the data buffer pool.
DATA DISK RD The number of pages that are not in the data buffer pool
at request time. The operating system must fetch these
pages, either from the operating system buffer pool or
by a physical disk read.
DATA DISK WR The number of dirty pages from the data buffer pool that
have been logically written to disk.
MISS RATE The percentage of pages that are not in the data buffer
pool, calculated as follows:
MISS RATE = (DATA DISK RD / BUFF ACCESS) * 100
PROGRAM NAME The name of the program being run.
All of the sessions running a program are listed beneath
the PROGRAM NAME.
AVERAGE For a given column, the average amount of work performed
by the processes in the list.
Each program has a list of processes beneath it. Each
process has a line of information, which shows
percentages in each column. The line shows the exact
percentages of work each process performs, in each
column. The AVERAGE field, however, shows the average
amount of work each process performs.
For example, in the above screen, process 1 is
responsible for 11% of the BUFF ACCESS activity in the
DBEnvironment, and process 3 is responsible for 87%. On
average, each process is responsible for 49% of the BUFF
ACCESS activity.
Related SET Commands
The SET commands in the following table affect this screen.
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| | | |
| Command | Description | Example |
| | | |
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| | | |
| SET REFRESH | Controls the refresh rate of the screen. | SET REFRESH 10 |
| | | |
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| | | |
| SET SORTIODATA | Sorts the programs in descending order | SET SORTIODATA 1 |
| | according to the value of the specified | |
| | column. | |
| | | |
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| | | |
| SET TOP | Limits the number of programs displayed. | SET TOP 5 |
| | | |
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MPE/iX 5.0 Documentation