Rick Troth <[EMAIL PROTECTED]> writes:
> Sounds a lot like XIP,  which is based on EXT2.
> Define a partition of the same size as the intended DCSS
> (or slightly less),  put your stuff there,  unmount it,
> use 'dd' or something like it to grab a snap-shot,  and store.

there was science center
http://www.garlic.com/~lynn/subtopic.html#545tech

report done on the initial port of vmm from cp67 to vm370

L. Wheeler, CSC VM/370 Extended II: Virtual Memory Management, IBM
Science Center Report ZZ20-6002, July 1974, 19 pp., shared segments,
migration.

the dcss subset of vmm
http://www.garlic.com/~lynn/subtopic.html#mmap

was then done for vm/370 release 3, 30 years ago.

vmm also included a lot of work on address independent
code:
http://www.garlic.com/~lynn/subtopic.html#adcon

mmap support allowed the use of the paging kernel support to directly
read/write any standard disk area. it eliminated a lot of the overhead
of simulating virtual i/o (among other things).

a little drift, i included some part of "migration" in the resource
manager.
http://www.garlic.com/~lynn/2001e.html#45 VM/370 Resource Manager

from above (taken from the "blue" letter):

Enhancements are made to VM/370 in these areas:

Scheduling ALgorithm. A fair share approach to distribute the
resources of the system equally among the users with improved
interactive performance on trivial commands.

Page Migration. Designation of preferred paging areas on DASD with
migration to other devices is based on how long the pages are unused.

Swaptable Migration. Seldom used segment tables are swapped to DASD
thereby freeing up main storage.

Reset Pages and Time Stamp Segments. The working set algorithm
improves page selection, while time stamping facilitates page
migration and swaptable migration.

Working Set Estimate. Dynamically adjusted multiprogramming levels are
achieved by periodic evaluation of total system performance based on
feedback control.

Fast Redispatch Extension. The number of cases where fast redispatch
implementation is used after privileged instruction simulation and I/O
interruptions are increased.

Enable Window. It increases the extent to which VM/370 runs enabled and
thus can accept I/O and external interruptions

Set Favored Extension. The specification of multiple users with the
set favored percent option is provided.

Indicate Command Extension. Additional performance status data is made
available to the systems performance evaluation routine.

Selective Path Length Reductions.

--
Anne & Lynn Wheeler | http://www.garlic.com/~lynn/

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