[email protected] (Anne & Lynn Wheeler) writes: > There was a problem as more and more services moved into virtual > machines (common terminology now calls it virtual applicance, but then > was called service virtual machines) ... that even if the system auto > re-ipl'ed w/o human intervention ... there was increasing need to have > the services running virtually automatically come up.
re: http://www.garlic.com/~lynn/2014g.html#85 Costs of core another part of the rise of the service virtual machines was SPM. cp67 had message mechanism to send instant/text message between users. SPM (special message) was originally developed for cp67 at the IBM Pisa science center ... and quickly was used for service virtual machines. user-to-user and system-to-user messages could be redirected to software running in the service virtual machine ... implementing all sorts of automated operations under program control. one of the original service virtual machines was vnet/rscs ... basis for the internal network (larger than arpanet/internet from just about the beginning until sometime late '85 or early '86) done by former coworker at the science center http://en.wikipedia.org/wiki/Edson_Hendricks as well as the technology used for the corporate sponsored univ. network (also for a period larger than arpanet/intenet) ... which is where ibm-main originated http://en.wikipedia.org/wiki/BITNET SPM allowed authorized users to send messages to RSCS/VNET and be interpreted as commands. RSCS/VNET also leveraged SPM to allow user-to-user messages across the network (message sent to local RSCS/VNET then forwarded to users on different machines). SPM was also used by the author of REXX to implement a multi-user client/server spacewar game ... spacewar server anywhere in the network, with clients communicating with the server (even leveraging RSCS/VNET forwarding to have spacewar communities across the network). The client interface was standard 3270 screen, keyboard commands and space map on the screen. A problem arose, the client/server interface was simple enough that several users wrote "bot" players ... that started to dominate all games. Eventually the server was modified that non-linearly increased power use as the interval between client commands dropped below typical human reaction time (somewhat leveling the playing field) SPM was the standard mechanism, leveraging the user-to-user message mechanism to implement all sorts of automated software services and automated operator. on of the problems was high resistance to releasing it to customers. A radical subset of SPM was released as IUCV ... and then a different subset as SMSG (however both IUCV plus SMSG combined was still a subset of full SPM). other recent posts mentioning service virtual machines http://www.garlic.com/~lynn/2014.html#1 Application development paradigms [was: RE: Learning Rexx] http://www.garlic.com/~lynn/2014.html#2 Application development paradigms [was: RE: Learning Rexx] http://www.garlic.com/~lynn/2014.html#18 "Death of the mainframe" http://www.garlic.com/~lynn/2014e.html#49 Before the Internet: The golden age of online service http://www.garlic.com/~lynn/2014f.html#86 Is end of mainframe near ? -- 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
