Not directly, but it also wouldn't prevent unnecessary page outs after page steals. A better new instruction would be an unpriviled instruction similar to IPTE; mark the page as invalid only if write is permitted, otherwise protection exception. Maybe even a version that also clears the page and sets a PTE that cause the next write to set it back to valid. The intent is to cause the OS to treat the page as valid but unmodified since allocation, and to avoid extraneous interrupts.
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Assembler List [[email protected]] on behalf of Paul Gilmartin [[email protected]] Sent: Thursday, April 14, 2022 1:26 PM To: [email protected] Subject: Re: Next instruction needed On Apr 14, 2022, at 11:06:09, Tom Harper wrote: > > IMHO, the next instruction to add to z/Architecture would be an instruction > to clear storage to zeros. > Would that cause a Lot of paging I/O? Would it be better to mark all pages as invalid, to be cleared automatically when referenced, if ever? That would be an O/S function, not hardware. -- gil
