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    SubjectRe: [PATCH v2 02/13] memcg: Kernel memory accounting infrastructure.
    On 03/13/2012 09:00 PM, Greg Thelen wrote:
    > Glauber Costa<> writes:
    >> 2) For the kernel itself, we are mostly concerned that a malicious container may
    >> pin into memory big amounts of kernel memory which is, ultimately,
    >> unreclaimable. In particular, with overcommit allowed scenarios, you can fill
    >> the whole physical memory (or at least a significant part) with those objects,
    >> well beyond your softlimit allowance, making the creation of further containers
    >> impossible.
    >> With user memory, you can reclaim the cgroup back to its place. With kernel
    >> memory, you can't.
    > In overcommit situations the page allocator starts failing even though
    > memcg page can charge pages.
    If you overcommit mem+swap, yes. If you overcommit mem, no: reclaim
    happens first. And we don't have that option with pinned kernel memory.

    Of course you *can* run your system without swap, but the whole thing
    exists exactly because there is a large enough # of ppl who wants to be
    able to overcommit their physical memory, without failing allocations.

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      Last update: 2012-03-13 18:35    [W:0.019 / U:2.220 seconds]
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