Subject: Re: nfs servers and 5 minute VOP_READ's
To: Frank van der Linden <firstname.lastname@example.org>
From: Bill Studenmund <email@example.com>
Date: 03/16/1999 13:55:26
On Tue, 16 Mar 1999, Frank van der Linden wrote:
> On Tue, Mar 16, 1999 at 12:28:19PM -0800, Bill Studenmund wrote:
> > I was hoping for something more like:
> > Client sends a request.
> > Server sees it can't service
> > Server tells client to try again later
> > Client keeps request around, and sleeps on it.
> > Client tries again.
> > Server sees if it can service. If not, server says try later.
> This is, in fact, what is supposed to happen.. NFSERR_JUKEBOX (for some
> reason called TRYLATER in our code; presumably because of a similarly
> named NQNFS construct) is the right one to use, and does, or is supposed
> to do, exactly what you want. The client should wait for a while and
> try again, using the same XID. Should've thought of that sooner..
> thankfully Roger pointed it out.
Cool. I think TRYLATER is used as it makes a lot more sense than JUKEBOX.
> The NetBSD client should do exponential backoff in this case. It's
> actually a piece of code that probably never was tested.. but
> it's simple, nothing much can go wrong (famous last words ;-))
How did the patches to add server support look? Obviously they aren't
right for a jukebox as-is, but they let the fs say "try later."