The following message is a courtesy copy of an article that has been posted to bit.listserv.ibm-main,alt.folklore.computers as well.
[email protected] (Mike Myers) writes: > Four of us teamed up to do a proof of concept by installing a running > CMS under MVS. We added a CMS command to TSO which caused TSO to > GETMAIN a sufficiently large area of storage from its own address > space and then to load the CMS nucleus in that storage. Using SIE, it > would dispatch the CMS nucleus. I implemented a CMS file system > mini-disk structure in VSAM using control area access and later > planned to use the VSAM actual block processor. I had earlier done a paged mapped filesystem for CMS on cp67 and then migrated to vm370 http://www.garlic.com/~lynn/2006v.html#email731212 http://www.garlic.com/~lynn/2006w.html#email750102 http://www.garlic.com/~lynn/2006w.html#email750430 and shipped internally to the "csc/vm" (and later "sjr/vm") internal customer sites. misc. past posts mentioning paged mapped file system http://www.garlic.com/~lynn/submain.html#mmap I also had done all sorts of fancy stuff with shared segments ... somewhat akin to tss/360 (or FS ... one of my less than complimentary comments about FS was that I had stuff already running that was better than what they were trying to do). However, a large part of CMS used os/360 conventions, assemblers & compilers which gave me lots of problems with some of the fancier features. misc past posts with discussions of some of those problems http://www.garlic.com/~lynn/submain.html#adcon the original intention was to use some of the fancier parts of the 370 virtual memory architecture. However, when 360/165 ran into schedule problems retrofitted virtual memory hardware to the 165 and the favorite son operating system in POK said they could see no reason for the fancier features ... they were droppes (as part of 165 picking up six months in schedule and allowing 370 virtual memory annoncement not to be delayed). The standard vm370 product was also going to make a little use of some of the new features ... but when they were dropped from the hardware product ... vm370 had to go back and do some ugly hacks to compensate. except for short time for pc/370 (xt/370, at/370) the page mapped stuff was never shipped outside the corporation ... even tho i can demonstrate extremely significant disk thruput and pathlenght improvements. I had some number of benchmarks showing identical applications running on identical 3380s ... ran three times faster with CMS paged mapped filesystem than with standard CMS filesystem. -- 42yrs virtualization experience (since Jan68), 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
