>> Of course judging that would require some more details, ie. what parts 
>> of UVM etc. you'd need to modify. I guess using some "compressed 
>> pages" thing as backing store should fit rather neatly in, and not be 
>> too "icky" for
>> an option or (pseudo)device.

Now this point has got me to thinking. Is the way that an object is 
written to backing store dictated by its uvm_pagerops structure? And if 
so, would creating a pseudo device with its own pager operations be a 
reasonable way to go about handling writing to the compressed cache? 
Surely this way the pseudo device would handle the compression and 
decompression of the pages for the object.

Although I suppose it would have to be in addition to the uvm_pagerops 
struct that an object already had (or else how would the compressed 
cache know how to write to the _real_ backing store?).

Does this seem like a feasible idea?

Thanks,
Matt