Re: [Linux-cachefs] Fedora kernel testing

[Daire Byrne <Daire Byrne framestore com>]

David,

----- "David Howells" <dhowells redhat com> wrote:

> The same applies to data cached from regular files.  How and when do
> you determine if it is obsolete?  There are two ways to do this:
> 
>  (1) Ask the server to notify you on change.  I don't know whether
> NFS4 provides leases on directories as it does for files.  With AFS,
> as with a file, you get a callback if a directory you have read gets
> modified, but I don't know if this is possible for NFS.
> 
>  (2) Poll the server occasionally, but less frequently than the
> accesses, if the accesses are very frequent.  That can be made configurable,
> and may already be partially implemented (see the 'lookupcache' mount
> option and also 'acdirmin' and 'acdirmax').

Well it looks like I need to really start benchmarking the VPN setup with
NFSv4. I have not looked at NFSv4 in ages but it looks like it now actually
works pretty well! My Fedora 10 client doesn't seem to know about the 
lookupcache mount option but I did find this interesting info:

  https://wiki.linux-nfs.org/wiki/index.php/NFSv4.1_Directory_Delegations

I will play around and see where I get to. Thanks for the help.

Daire