Sirius Satellite Radio SirFile 204, Руководство пользователя

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Overview and Setup for SirFile
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CHAPTER 2
Overview and Setup for SirFile
SirFile is a comprehensive facility for monitoring the physical storage utilization of
Model 204 database files and warning users of the need for file reorganizations.
SirFile requires only a single screen of setup information to determine “thresholds,” after
which it automatically performs a pass through the online database files, checking to see
if any file has exceeded a threshold. The process that evaluates files is called the
refresh process . The refresh process performs two types of checks:
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It compares the current state of each file against the threshold settings to see if any
file statistic is above the critical value for that statistic.
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It maintains a database of table usage information which it uses to determine rate of
growth and to predict when thresholds will be exceeded.
During the initial database load, all files added to the SirFile database are compared to
the system default thresholds. After the initial load, the user may override the system
default thresholds with file-specific thresholds for files that require higher or lower levels
of monitoring.
If any file table is above a threshold, SirFile flags the file with a warning, causing it to be
highlighted in SirFile . Once SirFile has stored at least one sample snapshot of a file, it
begins calculating the date at which each table will fill — assuming any table is showing
growth. If the predicted fill date falls within a user-settable number of days, SirFile posts
a prediction to the file, and the file is highlighted in the SirFile screens. When a
prediction or warning is posted using a periodic refresh, a message can also be sent to
the audit trail, as well as to a list of user IDs.
The file parameters that are evaluated for table-full status are ARETRIES, BFULLP,
CRETRIES, CFULLP, DFULLP, EXTNADD, OVFLADD, EOVFLADD, and SPILLADD.
The database refresh portion of SirFile is quite efficient, however it is the most expensive
operation in SirFile . Therefore, several options are provided for determining when to
perform a refresh, and for determining when to calculate CFULLP, generally the most
expensive of the refresh calculations.
For more information, see:
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“The Refresh Process” on page 11 , for a complete description of the refresh process
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“Invocation Techniques for Background Monitoring” on page 33 , for methods that
invoke a periodic refresh
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SirFile User's Guide 5