[dm-devel] dm-cache + storage client experiment

[John Stoffel]

>>>>> "mlody3k" == mlody3k  <mlody3k at gmail.com> writes:

mlody3k> Hi dm developers!
mlody3k> I'm during the experiment with dm-cache and storage client and I would be very grateful if some of
mlody3k> You will help me with some of my questions :). 

mlody3k> Simply, I would like to implement the write-through caching in the client where:
mlody3k>  - dm-cache is only responsible to check whether requested data is in the cache device (return
mlody3k> requested data if hit, ENODATA if miss - do not read from origin) - in case of miss, my client
mlody3k> will read data from the origin.
mlody3k>  - dm-cache will write only to the cache device - client will write data to the origin.

So instead, why don't you just have two different mount points, one
being /cache, the other being /slow, and have your app look for data
in /cache first, then pull from /slow.  If you write data, then you
just write it yourself where you want.

dm-cache is more of a block level tool, and you're looking for more of
a file level tool from what I can see.

Probably what you really want is to be able to tune and tweak the
algorithm inside dm-cache to do what you want.  In that case, I don't
have a clue how this would happen unfortunately.