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Re: [Xen-devel] windows tmem

> I am not familiar with the Windows APIs, but it sounds like you
> want to use the tmem ephermeal disk cache as an secondary cache
> (which is BTW what Linux does too).
> That is OK the only thing you need to keep in mind that the
> hypervisor might flush said cache out if it decides to do it
> (say a new guest is launched and it needs the memory that
> said cache is using).
> So the tmem_get might tell that it does not have the page anymore.

Yes I've read the brief :)

I actually wanted to implement the equivalent of 'frontswap' originally by 
trapping writes to the pagefile. A bit of digging and testing suggests it may 
not be possible to determine when a page written to the pagefile is discarded, 
meaning that tmem use would just grow until fill and then stop being useful 
unless I eject pages on an LRU basis or something, so ephemeral tmem as a 
best-effort write-through cache might be the best and easiest starting point.


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