Text File

Aucbvax.4745 fa.unix-wizards utzoo!decvax!ucbvax!unix-wizards Wed Oct 28 01:18:17 1981 Partitioned Memory for Unix >From mike.bmd70@BRL Wed Oct 28 00:30:37 1981 Greg -

There is a Naval Postgraduate School Thesis entitled "The Development of a Partitioned Segmented Memory Manager for the UNIX Operating System", by Harvey William Emery, Jr, dated June 1976, which discusses the subject in some detail, and reviews an implementation which they put together to test their theories.

[Copies can be had from the Defense Documentation Center, Defense Logistics Agency, Cameron Station, Alexandria, VA; Document ADA027251]

"ABSTRACT. This thesis reports the results of an investigation of the applicability of pagin and segmentation to memory management in modified UNIX operating systems on the PDP-11/50.... Two memory managers are specifically considered: a partitioned segmented memory manager that was designed and implemented; and a simpler, sgemented memory manager that was designed based on the performance of the partitioned segmented memory manager. Recommendations are given for future work."

The conclusions of the report are rather vague, but seem to indicate that PSUNIX (their paged swap UNIX) did not cost anything in terms of performance overall. It appears that the extra cost of the repeated PHYSIOs and calls on the driver was offset by the better memory utilization on the 256Kb 11/50.

I can try to provide more info on this if people are interested... Cheers, -Mike

----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen <jgoerzen@complete.org> of http://communication.ucsd.edu/A-News/

This Usenet Oldnews Archive article may be copied and distributed freely, provided:

1. There is no money collected for the text(s) of the articles.

2. The following notice remains appended to each copy:

The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.