How to pass sort options to the sort utility invoked by Secondary Index Builder

Document ID : KB000025075
Last Modified Date : 14/02/2018
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Question:

How can Sort options be passed to an external Sort utility (e.g. CA-SORT, DFSORT, SYNCSORT) which will be invoked during SIB (Secondary Index Builder) execution.

Answer:

DD statements SORTCNTL (for CA-SORT) or DFSPARM (for DFSORT and SYNCSORT) can be used in the SIB step JCL to pass information about the record length and the estimated record count, which enables the sort utility to run with better performance and less SORTWORK space.

If SIB is used to create the Index Databases after recovering a main Database and if the longest Index record is 50 Bytes and the estimated number of Sort records is 10.000.000, these options should be passed to the DFSORT Sort utility via DFSPARM DD statement :

//DFSPARM DD *
RECORD TYPE=V,LENGTH=(50);
OPTION FILSZ=E10000000

Additional Information:

Note SORTCNTL or DFSPARM DD are ONLY necessary with Secondary Index Builder (SIB). If the Database Organizer tool (DBO) is executed(which also can invoke the Sort utility), options AVGRLEN and FILSZ are available with DBO to pass this information to the Sort utility, so DD statements SORTCNTL or DFSPARM will not be necessary in this case.