Messages in this thread | | | Date | Thu, 8 Apr 2004 11:50:43 +1000 | From | David Gibson <> | Subject | Re: RFC: COW for hugepages |
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On Wed, Apr 07, 2004 at 02:34:47PM +0200, Andi Kleen wrote: > On Wed, 7 Apr 2004 17:42:39 +1000 > David Gibson <david@gibson.dropbear.id.au> wrote: > > > Currently the kernel does not implement copy-on-write for huge pages - > > in fact any sort of page fault on a hugepage results in a SIGBUS. > > This means that hugepages *always* have MAP_SHARED semantics, even if > > MAP_PRIVATE is requested, and in particular that they are always > > shared across a fork(). Particularly when using hugetlbfs as just a > > source of quasi-anonymous memory, those are rather strange semantics. > > [...] > > Implementing this for ppc64 only is just wrong. Before you do this > I would suggest to factor out the common code in the various hugetlbpage > implementations and then implement it in common code.
Yes, I know it needs to be implemented for the other archs, but I wanted to get some feedback on the concept before diving into the other arch details to figure out how to implement it there.
-- David Gibson | For every complex problem there is a david AT gibson.dropbear.id.au | solution which is simple, neat and | wrong. http://www.ozlabs.org/people/dgibson - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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