Monitoring the Buffer Caches

Buffer cache performance is a key factor in overall performance. Buffer cache monitor logs buffer cache, memory, and I/O statistics.

Use the buffer cache monitor to fine-tune main and temp buffer cache memory allocation. If one cache performs significantly more I/O than the other, reallocate some of the memory in small amounts, such as 10 percent of the cache allocation on an iterative basis. After reallocating, rerun the workload and monitor the performance changes.

• Starting the Buffer Cache Monitor
  Run the buffer cache monitor from Interactive SQL. Each time you start the monitor it runs as a separate kernel thread within Sybase IQ.
• Output Options
  Buffer cache monitor output depends on the switches you include with the monitor_options argument.
• Checking Results While the Monitor Runs
  On UNIX systems, you can watch monitor output as queries are running.
• Stopping the Buffer Cache Monitor
  The command you use to stop a monitor run is similar to the one you use to start it, except that you do not need to specify any options.
• Examining and Saving Monitor Results
  Buffer cache monitor logs the results of each run.