Hi!

> > Seems frontswap is like a reverse balloon, where the balloon is in
> > hypervisor space instead of the guest space.
> 
> That's a reasonable analogy.  Frontswap serves nicely as an
> emergency safety valve when a guest has given up (too) much of
> its memory via ballooning but unexpectedly has an urgent need
> that can't be serviced quickly enough by the balloon driver.

wtf? So lets fix the ballooning driver instead?

There's no reason it could not be as fast as frontswap, right?
Actually I'd expect it to be faster -- it can deal with big chunks.

-- 
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