Lynn, I signed in to LinkedIn and was unable to find the reference, so thanks for including the URL for the missing LinkedIn reference. I read through that reference and saw 16 comments, only one of which mentioned very bad throughput for CKD disks. No technical explanation was given for the bad throughput; i.e., was it hardware limitations in CKD, software limitations in Oracle, etc.? This comment was posted 23 days ago, ca. 28 years after IBM first announced ECKD and forward-thinking users began planning to junk their CKD by going to ECKD.
I remember many problems with ECKD when first implemented, just as there were many problems with OS/360 in the late 1960s, with MVS in the late 1970s, with the new VSAM catalog structure in the early 1980s, etc. But all those problems were addressed, code and hardware were redesigned, etc. I still stand by my earlier post - most users DID junk their CKD several decades ago. Why was this one shop still using CKD 28 years after CKD's replacement first appeared? Is this installation also running with a 28-year-old version of their operating system? I also sent this same question-comment into the LinkedIn thread. Bill Fairchild Rocket Software -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Anne & Lynn Wheeler Sent: Tuesday, March 22, 2011 12:17 PM To: [email protected] Subject: Re: junking CKD; was "Social Security Confronts IT Obsolescence" [email protected] (Bill Fairchild) writes: > It was. ECKD was announced in the early- to mid-80s, which was 25+ > years ago, which is several decades ago. Not all users respond > quickly. re: http://www.garlic.com/~lynn/2011e.html#31 "Social Security Confronts IT Obsolescence" oh, the missing linkedin URL reference: http://lnkd.in/ajGuA2 reference was to "CKD" disks didn't change ... controllers added some extra stuff (eckd) ... originally for "Calypso" ... the 3880 controller speed-matching buffer ... allowing 3380/3880 3mbyte connenction to (370/168 2880) 1.5mbyte channels ... which had enormous problems (that wouldn't/don't exist w/FBA). old email discussing calypso (eckd) and how bad the problems were (several severity ones in the field): http://www.garlic.com/~lynn/2007e.html#email820907b above also mentions the dismal prognosis of ever getting MVS to support FBA (I've periodically mentioned in the past about being told that even if I provided MVS with fully integrated & tested FBA support, I still needed $26M business case to cover education and pubs ... and I couldn't use lifecycle savings ... only incremental new sales). past posts with references to calypso/eckd: http://www.garlic.com/~lynn/2004o.html#7 Integer types for 128-bit addressing http://www.garlic.com/~lynn/2007e.html#40 FBA rant http://www.garlic.com/~lynn/2007f.html#0 FBA rant http://www.garlic.com/~lynn/2008q.html#40 TOPS-10 http://www.garlic.com/~lynn/2009k.html#44 Z/VM support for FBA devices was Re: z/OS support of HMC's 3270 emulation? http://www.garlic.com/~lynn/2009p.html#11 Secret Service plans IT reboot http://www.garlic.com/~lynn/2010e.html#36 What was old is new again (water chilled) http://www.garlic.com/~lynn/2010h.html#30 45 years of Mainframe http://www.garlic.com/~lynn/2010n.html#14 Mainframe Slang terms -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
