Monitoring the buffer caches
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starts monitoring of the temp buffer cache, for the Temporary Store
PRIVATE
of the database you are connected to. You need to issue a separate command to
monitor each buffer cache.
dummy_table_name can be any IQ table. However, it's a good idea to create a
table that you use only for monitoring. The table name is required for syntactic
compatibility with other
you specify, you are monitoring buffer caching for all tables in a database.
'monitor_options' can include one or more of the following values:
•
displays summary information for both the main and temp
-summary
buffer caches. If you do not specify any monitor options, you receive a
summary report. The fields displayed are as described for the other
options, plus the following:
•
Users: Number of users connected to the buffer cache
•
IO: Combined physical reads and writes by the buffer cache
•
displays activity in detail for the main or temp buffer cache. The
-cache
fields displayed are:
•
Finds: Find requests to the buffer cache
•
Creats: Requests to create a page within the database
•
Dests: Requests to destroy a page within the database
•
Dirty: Number of times the buffer was dirtied (modified)
•
HR%: Percentage of above satisfied by the buffer cache without
requesting any I/O
•
BWaits: Find requests forced to wait for a busy page (page frame
contention)
•
ReReads: Number of times the same portion of the store needed to be
reread into the cache within the same transaction
•
FMiss: False misses, number of times the buffer cache needed
multiple lookups to find a page in memory. This number should be 0
or very small. If the value is high, it is likely that a rollback occurred,
and certain operations needed to be repeated
•
Cloned: Number of buffers that Adaptive Server IQ needed to make a
new version for a writer, while it had to retain the previous version for
concurrent readers
commands. No matter what table name
IQ UTILITIES