info-vax@ucbvax.ARPA (03/21/85)
From: Tom Melton <tom@tove> Is the system page table swappable? It seems that it would not be since it is physically addressed. If this is so the system page table (which is 1/128th of the size of used system virtual space (including all page tables for all processes for all users, and the kernel)) is permanently resident. Is this true? How much does it tend to amount to on ULTRIX? For comparison, how much does it tend to amount to on VMS? More generally: I am trying to figure out the UNIX 4.2BSD (aka ULTRIX) memory management. Does anyone know of a good reference I should get? Thanks, Tom Melton University of Maryland Computer Science Department ARPA tom@tove tom@maryland UUCP ...decvax!seismo!umcp-cs!tom
info-vax@ucbvax.ARPA (03/22/85)
From: sasaki@harvard.ARPA (Marty Sasaki)
The best place to start with understanding virtual memory is the
"VAX Architecture" book. This will tell you how addresses get
translated in gory detail.
Briefly, the system page table is always memory resident. The system
itself can page. A processes page table is in the system virtual address
space.
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Marty Sasaki net: sasaki@harvard.{arpa,uucp}
Havard University Science Center phone: 617-495-1270
One Oxford Street
Cambridge, MA 02138