On 2/23/2018 11:45 AM, Paul Birkel via cctalk wrote: Speaking of lonnnnnng response times.... In the 1970s, during the development of a home-grown database system where I used to work (developed shortly before I started there in the mid 1970s) - that lasted over 40 years - on an IBM 360/65 MP, they were used to having the nascent DBMS and/or the application crash, so they got used to pressing Enter, waiting a minute or so, then heading down to the computer room to pick up the core dump. Well one day they got down to the computer room, but the DBMS was still running, so they headed back upstairs (one floor up). After about FIVE MINUTES the application they were using to test came back with the correct results. Mixed emotions: yeah, it worked, but whoa, performance was clearly going to be a problem. ;) By the time the thing was in production it had its own memory manager instead of using the OS/360 GETMAIN SVC, KORMAN (or "Harvey" for short ;)). Then it got its own task manager / threading to use instead of the OS/360 task management - TASKMAN (they really should have called it TAXMAN ;)). Then it got its own subsystem for loading the application programs, aka content management - yup - KONMAN. ;) So, in the end, it was almost an OS unto itself. [I served as the DBA for 7 years during that time.] Starting out under OS/360 MVT, it survived moves and garnered enhancements under MVS, MVS/SP, MVS/XA, MVS/ESA, OS/390 and finally z/OS before it was finally retired.