Messages in this thread | | | Subject | Re: [RFC PATCH v2 00/30] 1GB PUD THP support on x86_64 | From | David Hildenbrand <> | Date | Fri, 2 Oct 2020 09:50:02 +0200 |
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>>> - huge page sizes controllable by the userspace? >> >> It might be good to allow advanced users to choose the page sizes, so they >> have better control of their applications. > > Could you elaborate more? Those advanced users can use hugetlb, right? > They get a very good control over page size and pool preallocation etc. > So they can get what they need - assuming there is enough memory. >
I am still not convinced that 1G THP (TGP :) ) are really what we want to support. I can understand that there are some use cases that might benefit from it, especially:
"I want a lot of memory, give me memory in any granularity you have, I absolutely don't care - but of course, more TGP might be good for performance." Say, you want a 5GB region, but only have a single 1GB hugepage lying around. hugetlbfs allocation will fail.
But then, do we really want to optimize for such (very special?) use cases via " 58 files changed, 2396 insertions(+), 460 deletions(-)" ?
I think gigantic pages are a sparse resource. Only selected applications *really* depend on them and benefit from them. Let these special applications handle it explicitly.
Can we have a summary of use cases that would really benefit from this change?
-- Thanks,
David / dhildenb
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