It's a mess, but not because of layer violations. Contemporary file-access protocols were far worse in that regard, as is ZFS in a different stack. I remember t

It's a mess, but not because of layer violations. Contemporary file-access protocols were far worse in that regard, as is ZFS in a different stack. I remember the XID-cache mess all too well from my younger days, but it's not really a layering issue. It's exactly the kind of thing that a session layer is supposed to do. That functionality can't be kept in the transport layer in the case of clustered servers (which I was working on at the time). Please don't use "layer-violating" just because it sounds bad.