that information; but tmem is trying to go a step further by makingKVM definitely falls into the camp of trying to minimize
the cooperation between the OS and hypervisor more explicit
and directly beneficial to the OS.
modification to the guest.
No argument there. Well, maybe one :-) Yes, but KVM
also heavily encourages unmodified guests. Tmem is
philosophically in favor of finding a balance between
things that work well with no changes to any OS (and
thus work just fine regardless of whether the OS is
running in a virtual environment or not), and things
that could work better if the OS is knowledgable that
it is running in a virtual environment.
For those that believe virtualization is a flash-in-
the-pan, no modifications to the OS is the right answer.
For those that believe it will be pervasive in the
future, finding the right balance is a critical step
in operating system evolution.
Is it the tmem API or the precache/preswap API layered on
top of it that is problematic? Both currently assume copying
but perhaps the precache/preswap API could, with minor
modifications, meet KVM's needs better?
range of normal perception". This is certainly not the first class
of memory in use in data centers that can't be accounted at
process granularity. I'm thinking disk array caches as the
primary example. Also lots of tools that work great in a
non-virtualized OS are worthless or misleading in a virtual
environment.