A bit late to the discussion but did the O.P. consider REPLACING the COBOL code with a pure DFSORT / ICETOOL implementation? That MIGHT remove duplicate data moves.
Such a process a customer and I worked together on last week took a 200 minute job and made it run in 10 minutes. YMMV. :-) Cheers, Martin Martin Packer, zChampion, Principal Systems Investigator, Worldwide Banking Center of Excellence, IBM +44-7802-245-584 email: martin_pac...@uk.ibm.com Twitter / Facebook IDs: MartinPacker Blog: https://www.ibm.com/developerworks/mydeveloperworks/blogs/MartinPacker From: Clark Morris <cfmpub...@ns.sympatico.ca> To: IBM-MAIN@listserv.ua.edu Date: 04/12/2013 15:57 Subject: Re: Has anyone measured CPU savings using external SORT's vs. internal (COBOL) SORT's? Sent by: IBM Mainframe Discussion List <IBM-MAIN@listserv.ua.edu> On 2 Dec 2013 06:14:42 -0800, in bit.listserv.ibm-main you wrote: >Sorry about the late reply. > >The last time I seriously looked, the COBOL sort verb invoked the installation sort (DFsort, SYNCSORT,....). > >The COBOL program effectively became the E15/E35 sort exits. > >On that basis, I would not expect any significant difference in CPU time consumed, *AND* as someone previously noted, a possible significant increase in elapsed time. > >HTH, > > ><snip> >It has been suggested to management here that there could be potentially significant CPU savings from re-engineering application programs such that any SORT's are done in a separate step, so that a program with a single internal SORT would be broken up into a pre-SORT process followed by an external SORT of the massaged data followed by a post-process of the SORTed data. ></snip> While the sort products do more efficient I/O than the standard access methods, this advantage is lost because an extra file may be written for the sort to read. In the past the major saving by using stand alone sorts was due to main memory limitations. By giving more memory to the sort the number of intermediate passes could be reduced. In today's environment that normally is not a consideration. Clark Morris > >---------------------------------------------------------------------- >For IBM-MAIN subscribe / signoff / archive access instructions, >send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN