Xref: utzoo comp.unix.wizards:22851 comp.unix.i386:6782 comp.sys.att:9975 Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!wuarchive!mit-eddie!bloom-beacon!eru!luth!sunic!mcsun!hp4nl!tuegate.tue.nl!tuewsd!wsinpdb From: wsinpdb@lso.win.tue.nl (Paul de Bra) Newsgroups: comp.unix.wizards,comp.unix.i386,comp.sys.att Subject: Re: Is VHANDFRAC --> VHANDL dynamic? Message-ID: <1289@tuewsd.win.tue.nl> Date: 13 Jul 90 10:56:40 GMT References: <562@oglvee.UUCP> <565@oglvee.UUCP> Sender: wsinpdb@win.tue.nl (Paul de Bra) Organization: Eindhoven University of Technology, The Netherlands Lines: 25 In article <565@oglvee.UUCP> jr@oglvee.UUCP (Jim Rosenberg) writes: >In pcg@cs.aber.ac.uk (Piercarlo Grandi) writes: >>... What happens is that the pger will make a distinction >>between active and *inactive* pages; and will put the *inactive* pages >>on the to-be-free list, ready to be reused, but it will not actually >>clean them out and reuse them unless there is demand for actually-free >>memory. > >Hello? Let me see if I understand this. The page-stealing demon will not >*really* move a page out to swap space unless a process actually *asks* for >more memory... I think this is wrong. The page-stealing demon will copy a page to swap space and mark it as 'free'. It does not zero the page or anything, so if the process wants the page back and the page has not been ackuired by another process in the meantime the original process can get its original page back. It need not be paged-in from the swap space. Is this correct? The problem which remains is what happens when a process suddenly needs more pages that are currently marked free. Paul. (debra@research.att.com)