[lkml]   [2008]   [Aug]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] coredump_filter: add hugepage core dumping

> > I think VM_RESERVED default dumping bahavior is good,
> > then I'd like to add coredump_filter mask.
> >
> > This patch doesn't change dafault behavior.
> This seems very reasonable to me
> (though I've little use for coredumps or hugepages myself).

Thanks a lot.

> One caution though: how well does it behave when coredumping a large
> area of hugepages which have not actually been instantiated prior to
> the coredump? We have that funny FOLL_ANON ZERO_PAGE code in
> follow_page() to avoid wasting memory on large uninstantiated anon
> areas, but hugepages won't go that way. If the dump hangs waiting for
> memory to be freed, or OOMkills other processes, that wouldn't be good;
> whereas if hugepage reservations (I've not followed what happens with
> them) or whatever just make it skip when no more, that should be okay.

I think hugepage reservation pages always exist when hugepage COW happend.
Then, hugepage access never cause try_to_free_pages() nor OOM.

Adam, if I talk lie, please tell us truth.

 \ /
  Last update: 2008-08-29 01:39    [W:0.158 / U:38.344 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site