[Gluster-devel] handling statfs call in USS

[Vijay Bellur]

On 12/24/2014 02:30 PM, Raghavendra Bhat wrote:
>
> Hi,
>
> I have a doubt. In user serviceable snapshots as of now statfs call is
> not implemented. There are 2 ways how statfs can be handled.
>
> 1) Whenever snapview-client xlator gets statfs call on a path that
> belongs to snapshot world, it can send the
> statfs call to the main volume itself, with the path and the inode being
> set to the root of the main volume.
>
> OR
>
> 2) It can redirect the call to the snapshot world (the snapshot demon
> which talks to all the snapshots of that particular volume) and send
> back the reply that it has obtained.
>

Each entry in .snaps can be thought of as a specially mounted read-only 
filesystem and doing a statfs in such a filesystem should generate 
statistics associated with that. So approach 2. seems more appropriate.

-Vijay