[email protected] (Clark Morris) writes: > While the last systems programming job I did was 27 years ago and I > wouldn't know how to safely power on and IPL a system today (3081s > didn't have LPARs let alone HMCs) that is ridiculous. At least I know > how to play with SMF 30 records in COBOL and modify other peoples > assembler code. I am not willing to move from Nova Scotia so I am not > looking for the job although I might take short assignments. > Retirement is nice.
3081 did have service processor which then had increasing functions. field engineering had diagnostic process that started with scoping individual components. 3081 had components in TCMs and could no longer (directly) scoped. For TCMs, service processors were introduced with probes into TCMs for doing diagnostics ... and engineers had bootstrap process starting with being able to (directly) scope/diagnose the service processor ... which then could be used to diagnose the 3081. 3090 service processor started out was to be 4331 running customized version of VM370 release 6 ... it was then changed to a pair of 4361. PR/SM (LPARs) was eventually introduced for 3090 as reaction to Amdahl's "hypervisor". Amdahl had created macrocode ... which was intermediate 370-like instructions ... and enormously easier to program than the native machine horizontal micrcode (originaly done to the increasing number of architecture tweaks that IBM was making). It was then used to implementation hypervisor (virtual machine subset). 3090 took quite a bit longer to respond to Amdahl's hypervisor (with PR/SM, LPAR) because it had to be done in the low-level native horizontal microcode. -- 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: INFO IBM-MAIN
