On Fri, Nov 19, 2004 at 07:07:12AM -0500, John Ellson wrote: > >but you can tell which pages are in memory at least. If people want I > >can code a small app for this > > > > > Don't go out of your way, but if you have some snippets of code I can > look at it would be appreciated. basically you want to use the mincore() syscall; it will tell you which parts of the file are in memory (you need to mmap it first). Note that this gives the status of the kernel page cache; so if you want a honest measurement you need to somehow clear that cache first (for example by unmounting + remounting the fs the library is on) > >no that happens always (even with the main binary btw); the difference > >prelink makes is that without prelink you need to touch (and thus load) > >more pages even if you don't use the library, for relocations. > > > > > So if I understand, deferred paging doesn't depend on prelinking, but if > I am going to try to measure > avoided-page-loads then I should make sure that prelinking has been done? I'd recommend that yes; you get a more "honest" answer since prelink is on by default in basically all modern distributions
