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Subject: Re: [PATCH RFC] mm/madvise: introduce MADV_POPULATE to
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From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat GmbH
Message-ID: <2073702b-9e09-2033-2915-628c7b7ccb3d@redhat.com>
Date:   Sat, 20 Feb 2021 10:01:00 +0100
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> Sorry, for jumping in late ... hugetlb keyword just hit my mail filters :)
> 

Sorry for not realizing to cc you before I sent out the man page update :)

> Yes, it is true that hugetlb reservations are not numa aware.  So, even if
> pages are reserved at mmap time one could still SIGBUS if a fault is
> restricted to a node with insufficient pages.
> 
> I looked into this some years ago, and there really is not a good way to
> make hugetlb reservations numa aware.  preallocation, or on demand
> populating as proposed here is a way around the issue.


Thanks for confirming, this makes a lot of sense to me now.


-- 
Thanks,

David / dhildenb