John, I have to disagree with you as concerns the efficiency of SORT I/O (of the main two SORT competitors at least) vs. statement level language I/O. In my experience, the proprietary EXCP (or even lower) level algorithms used by SORT will almost always exceed the efficiency of even the best-written HLL applications program. SORT can do things at a level just not available (or not easily available) to the general programming public. I think it would not be inaccurate to state that channel programming is just not in the skill set of 99.99% of programmers, and due at least to privilege requirements is not usually available to a programmer even if they have the skill set.
The observed performance numbers speak for themselves. My admittedly unscientific observations have always seen a decrease in consumed resources *on the same task* for SORT vs. any HLL I have ever used, and in very large volume cases I generally see quite large decreases. I also admit that for small data volumes the observed decrease in resource usage may not be (easily) observable. I can certainly agree with your comment on the ultimate usefulness of bureaucratic controls alone as error-reduction mechanisms. Peter > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On > Behalf Of John Gilmore > Sent: Monday, November 21, 2011 6:14 PM > To: IBM-MAIN@bama.ua.edu > Subject: Re: Simple record extraction from a sequential file > > I am not at all hostile to DFSORT, which I now prefer slightly to > SYNCHSORT. > > I am, however, hostile to the notion that I/O in a statement-level > language is always inferior to that of DFSORT. Here both of my young > programmers used a locate-mode READ-SET for the input records, > examined each in its buffer, and an effectively asynchronous move-mode > WRITE-TO a LOCATEd position in an output buffer for the selected > records. Their JCL included appropriate BUFNO=, etc. > (Interestingly, something very similar could be but in fact is almost > never done in COBOL with a reusable C or PL/I driver.) > > I am of course familiar with production-control schemes. Production > must be orderly, but in my experience bureaucratic controls alone do > not reduce errors: They only diffuse responsibility. -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
