If you consider me one of the SORT experts, I have been involved with sort development since the early 80's, and never once ran a tape sort.
When I first worked for Liberty Mutual Insurance, we had a 7074 hypervisor running on a 360/65 and I saw a tape sort running there, but never wrote any code for it or the Syncsort version. Chris Blaicher Technical Architect Mainframe Development Syncsort Incorporated 2 Blue Hill Plaza #1563, Pearl River, NY 10965 P: 201-930-8234 | M: 512-627-3803 E: cblaic...@syncsort.com www.syncsort.com CONNECTING BIG IRON TO BIG DATA -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Paul Gilmartin Sent: Monday, February 6, 2017 1:55 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: BSAM vs QSAM (and SORT). On 2017-02-06, at 07:22, R.S. wrote: > > It's worth to mention that performance of reverse processing dataset on real > tape is worse than horrible. > And IMHO it's not argument for using virtual tapes but for not using datasets > on tape for applications. Tapes are for backup and ML2. > I had understood that old-fashioned SORT with SORTWK on tape employed read backwards very effectively. Perhaps the SORT expert will jump in: https://en.wikipedia.org/wiki/Oscillating_merge_sort It was spectacular to watch. Are the data un-reversed by hardware, firmware, or software? On 2017-02-06, at 10:24, Binyamin Dissen wrote: > Also, reading a PDS member by member requires BPAM (which is really BSAM). > Which was our motivation, when I was in a small group supporting a FOSS compiler and runtime library, for implementing BPAM and BSAM but not QSAM. Once we had the BPAM interface, most of the interface could likewise be used for BSAM. Ironically, not burdened by the extreme storage constraints of OS/360, our compiler eschewed most of BPAM. At a COPY-type operation we simply opened another DCB, processed the member to the end, then popped back to the parent member; no NOTE or POINT involved. Worked great on MVS; not at all on CMS "OS Emulation". -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ________________________________ ATTENTION: ----- The information contained in this message (including any files transmitted with this message) may contain proprietary, trade secret or other confidential and/or legally privileged information. Any pricing information contained in this message or in any files transmitted with this message is always confidential and cannot be shared with any third parties without prior written approval from Syncsort. This message is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any use, disclosure, copying or distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and/or Syncsort and destroy all copies of this message in your possession, custody or control. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
