IO Data Session Screen [ ALLBASE/SQL Performance and Monitoring Guidelines ] MPE/iX 5.0 Documentation
ALLBASE/SQL Performance and Monitoring Guidelines
IO Data Session Screen
This screen provides data buffer pool I/O information for each session
attached to the DBEnvironment.
Click here to view figure.
To invoke the IO Data Session screen, use the d s command from the IO
subsystem, or use the /i d s 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 sessions are sorted. The
sessions are sorted in descending order by the value in
the column indicated by the asterisk. In the above
example, sessions are sorted by their 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
were logically written to disk.
MISS RATE The percentage of pages that are not in the data buffer
pool at request time. The percentage is calculated as
follows:
MISS RATE = (DATA DISK RD / BUFF ACCESS) * 100
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 5 |
| | | |
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| | | |
| SET SORTIODATA | Sorts sessions in descending order | SET SORTIODATA 2 |
| | according to the value of the specified | |
| | column. | |
| | | |
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| | | |
| SET TOP | Limits the number of sessions displayed. | SET TOP 10 |
| | | |
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MPE/iX 5.0 Documentation
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