[Bug other/50636] GC in large LTO builds cause excessive fragmentation in memory map

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50636

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-10-06 21:29:07 UTC ---
Perhaps on Linux, at least with recentish kernel, we could change release_pages
into keeping the pages in the G.free_pages chain, but call madvise
MADV_DONTNEED on the pages (and remember that we've done that so next
release_pages won't do it again unless we have since then alloc_page'd it).  At
least on 64-bit hosts where there is plenty of address space.  MADV_DONTNEED
will keep it around unless the kernel needs it for something else (something
e.g. glibc malloc uses too).