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From: Julian S. <js...@ac...> - 2004-09-02 10:35:27
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(/me is getting a bit confused here) Let me see if I have this right. If we simply implement Nick's original proposal, then the whole issue of reading debug info becomes moot because V can mmap in executables of any size to read their debug info. At least, assuming some contiguous, suitably large piece of virtual address space >= client_end can be found. This is an improvement on the current situation wherein we essentially are reserving 256M of space for more or less this purpose (+ misc other V-internal storage), and have to fail on executables bigger than ~200M. Do I understand right? J On Wednesday 01 September 2004 22:48, Nicholas Nethercote wrote: > On Wed, 1 Sep 2004, Jeremy Fitzhardinge wrote: > >> But when Nicholas said "incremental loading", he meant loading > >> debug infos for sections/compile units as we need them. > >> That's another problem, not completely decorrelated with > >> the "I can't map the whole file to read dbg infos". > > > > Yes, I know, exactly. > > Er, no, by "incremental loading" I meant loading the debug info for a > single section in pieces, rather than requiring one big mmap(). Loading > debug info as we need them I would call "lazy" or "on-demand" loading. > Sorry if that was unclear. > > >> Not sure it's worth doing it for now. How many people still use > >> stabs (on the platform we support...) ? > > > > Valgrind's dwarf support is pretty weak compared to the stabs support - > > there's nothing there to extract type information. > > But Helgrind is the only tool that uses the type information, and not many > people use Helgrind. > > > We only need to resort to padding things out either before we gain full > > control (constraining ld.so to put things in the right place) > > I'm surprised that people with non-overcommitting kernels are not having a > problem with this step, but are having a problem with the big-bang shadow > memory allocation. I would have thought the padding done by stage1 would > involve more than 1.5GB worth of maps. > > >> BTW, now we are speaking of mem layout, I think it is very important > >> to keep in mind that it would be great to bootstrap V... > > > > You mean self-virtualization? That's a goal, but its tricky. > > PIE should help, though. > > N > > > ------------------------------------------------------- > This SF.Net email is sponsored by BEA Weblogic Workshop > FREE Java Enterprise J2EE developer tools! > Get your free copy of BEA WebLogic Workshop 8.1 today. > http://ads.osdn.com/?ad_id=5047&alloc_id=10808&op=click > _______________________________________________ > Valgrind-developers mailing list > Val...@li... > https://lists.sourceforge.net/lists/listinfo/valgrind-developers |