:> [ML] It is possible to handle these cases in VM code, by :> trapping on any access to the partial page, and allowing only those :> accesses which are withing the originally requested range. Performance :> would suck without end, though. : :Well it would only suck for access to that page right, which wouldn't be too :bad unless the program in question thrashes out the partial pages. : :--- :Daniel O'Connor software and network engineer
I don't think this would be workable. It would fail utterly on small files -- every single access would be trapped. The system must be reasonably deterministic. Programmers have a reasonable expectation that accesses to mmap'd areas are, for in-core pages, instantanious. Otherwise they wouldn't bother to use mmap and instead would use read() and write() :-) -Matt To Unsubscribe: send mail to majord...@freebsd.org with "unsubscribe freebsd-hackers" in the body of the message