make the experimental NFS subsystem the default one

[Rick Macklem]

> 
> I've hacked up the old NFS server a bit to better serve my ESX/NFS
> needs (forcing it to always write async so it works faster with ZFS
> and a ZIL). I guess I could do the same to the new code as well...
> 
> ..However, if you didn't mind adding switch to force the NFS server to
> quietly only do an async VOP_WRITE, that would be really handy. Very
> dangerous for some people, but then again, so are most switches if you
> don't understand what they do. ESX will only opens it's files with
> O_SYNC, and it's not an editable option, so people like me running
> ESX+NFS over a ZFS share that has a ZIL are making the system do a lot
> of unnecessary sync writes. Yes, I know about SSD/RAM for the ZIL, but
> it still slows it down quite a bit over an async write.

Have you tries the "async" mount option on the client side?
(or did you say you couldn't do that above?)

I would be very hesitant to do it on the server side, since it would
violate the RFC (and you do run a risk of losing data, which many might
not realize uptil it is too late).

rick