Increasing the server wsize/rsize

[Neil Brown]

On Tuesday July 25, gnb at melbourne.sgi.com wrote:
> On Tue, 2006-07-25 at 02:35, Chuck Lever wrote:
> > On 7/23/06, Greg Banks <gnb at melbourne.sgi.com> wrote:
> > > On Tue, 2006-07-04 at 20:12, Greg Banks wrote:
> > > > On Tue, 2006-07-04 at 00:24, Chuck Lever wrote:
> > > > > Only a small nit:  when adding these #defines, can you include
> > > > > parenthesis around the definitions [eg. (6) and (4)] as you did with
> > > > > the newly added #defines?
> > > >
> > > > Sure, see below.
> > > >
> > >
> > > Are there any further comments on this patch?  If not I'll
> > > formally submit the latest version to Neil.
> > 
> > Greg-
> > 
> > Did you decide not to move the auth header definitions?
> 
> No, I just forgot.  DoH!  New patch below.
> 
> --
> Make knfsd support rsize/wsize of up to 1MB, over TCP.
> The limit over UDP remains at 32K.  Also, make some of
> the apparently arbitrary sizing constants clearer.
> 

So where are we up to with this?  Should I consider this a formal
submission yet???

One thought I have is that this will unconditionally require 1 Meg of
RAM to be allocated and pinned for each nfsd thread, which is slightly
more than the current 40K or so.  Do we really want to do that?

Part of me say that this upper limit should be configurable and should
default to something comfortable.
Another part of me says that having tuning knobs is usually more of a
pain than a gain.
Maybe the auto-tuning should be based on ram size
 < 256Meg -> default to 32K
 < 2Gig   -> default to 512K
 > 2Gig   -> default to 1Meg

or something like that.

Also, should svc_max_payload be 'static inline' in a header?
It isn't large and is only called 7 times (I think).

NeilBrown