Tuning the create image copy process

You can tune the create image copy process invoked by the FABJMAIN program.

I/O Buffer tuning for input data sets

The default value of the I/O buffer of the input image copy data set is BUFNO=15.

The buffer numbers depend on what tape unit is being used. If the input image copy data set resides on a DASD, you can improve the performance by increasing the buffer numbers.

The buffer number can be changed by specifying the value for BUFNO using the DSBUF keyword in the ICEIN control statement. If dynamic allocation is not used, specify BUFNO using the JCL DD card of the input image copy database data set.

Buffer tuning for output data sets

The default value of the I/O buffer for the output image copy data set is BUFNO=15.

The buffer numbers depend on what tape unit is being used. If the output image copy data set resides on a DASD, you can improve the performance by increasing the buffer numbers.

The buffer number can be changed by specifying the value for BUFNO using the ICBUF keyword in the ICEIN control statement. If dynamic allocation is not used, specify BUFNO using the JCL DD card of the output image copy database data set.