BHTO parameter (buffer handler timing)

The high ratio of buffer handler calls to application program DL/I calls in IMS makes separate collection of buffer handler CPU very CPU-intensive for the product. The ratio can be as high as 20 to 1, so collecting separate CPU time data for each buffer handler request can become too expensive when compared with the worth of the data. Depending on the number of database calls and the amount of buffer handler activity, BHTO=ON can increase CPU usage by 20 to 40 percent.

Syntax

Options

Valid options are:

• OFF (default)

  The buffer handler time (BHT) data is included with the DL/I CPU time data. The OFF option is forced if the DBIO option is not BFALTERS.

  DEDB and MSDB BHT for IMS Fast Path is always included in DL/I CPU time data.

  The Performance Reporter and the Transaction Accountant report BHT CPU=0. The Performance Reporter, the Transaction Accountant, and the Workload Analyzer trace services report increased DL/I CPU time (DL/I CPU = DL/I + BHT), which produces increased chargeable CPU time in the Transaction Accountant. Workload Analyzer trace services report increased DL/I CPU time (DL/I CPU = DL/I + BHT).

• ON

  The BHT data is collected separately. BHT data is available for the Performance Reporter and the Transaction Accountant.