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  * *cooperating with the VM when memory pressure increases*

  * *notify user applications of virtual memory events via real-time signals*

<http://www.cs.umass.edu/~emery/pubs/bookmarking-collector/>, and discussion at
<http://lambda-the-ultimate.org/node/2391> and
<http://marc.info/?t=113269321800003&r=1&w=2>.

Found this via <http://lambda-the-ultimate.org/node/4094#comment-62100>, which
was linked from [LWN](http://lwn.net/Articles/409416/).

From a quick glance, this sounds to [[me|tschwinge]] quite a bit like
mechanisms also found in (originating in?) Mach's
[[microkernel/mach/external_pager_mechanism]].  May be worth having a look at
it.


# IRC, freenode, #hurd, 2013-03-06

    <braunr> tschwinge: from a quick look, this isn't similar to the external
      pager mechanism
    <braunr> it's an additional tool to help userspace application manage
      internal caches
    <braunr> it's similar to what is done to reclaim memory from the slab
      allocator for example
    <braunr> and it would indeed be a very good thing to have so that e.g. the
      hurd can build a distributed but completely dynamic dentry-like cache
    <braunr> i'm actually glad to see someone else thought of using real time
      signals for this
    <braunr> i didn't do any research on that subject yet