Starting the buffer cache monitor

You run the Sybase IQ buffer cache monitor from Interactive SQL. Each time you start the monitor it runs as a separate kernel thread within Sybase IQ.

Use this syntax to start the monitor:

IQ UTILITIES { MAIN | PRIVATE }
 INTO dummy_table_name 
 START MONITOR 'monitor_options [ … ]'

MAIN starts monitoring of the main buffer cache, for all tables in the IQ Store of the database you are connected to.

PRIVATE starts monitoring of the temp buffer cache, for all tables in the Temporary Store of the database you are connected to.

You need to issue a separate command to monitor each buffer cache. You must keep each of these sessions open while the monitor collects results; a monitor run stops when you close its connection. A connection can run up to a maximum of two monitor runs, one for the main and one for the temp buffer cache.

dummy_table_name can be any Sybase IQ base or temporary table. The table name is required for syntactic compatibility with other IQ UTILITIES commands. It is best to have a table that you use only for monitoring.

To control the directory placement of monitor output files, set the MONITOR_OUTPUT_DIRECTORY option. If this option is not set, the monitor sends output to the same directory as the database. All monitor output files are used for the duration of the monitor runs. They remain after a monitor run has stopped.

Either declare a temporary table for use in monitoring, or create a permanent dummy table when you create a new database, before creating any multiplex query servers. These solutions avoid DDL changes, so that data stays up on query servers during production runs.

NoteTip To simplify monitor use, create a stored procedure to declare the dummy table, specify its output location, and start the monitor.

'monitor_options' can include one or more of the following values:

NoteThe interval, with two exceptions, applies to each line of output, not to each page. The exceptions are -cache_by_type and -debug, where a new page begins for each display.