Re: NFS and kernel 2.6.x

[Andrew Morton <akpm@osdl.org>]

Trond Myklebust <trond.myklebust@fys.uio.no> wrote:
>
> På to , 15/04/2004 klokka 18:14, skreiv Charles Shannon Hendrix:
> > 
> 
> > NFS server:
> > 
> >     Sun SS5
> >     10baseT ethernet (100baseT card available, not used)
> >     NetBSD 1.6.1
> >     pretty much a plain vanilla server setup
> > 
> > Network:
> > 
> >     simple LAN with three machines, connected via a full duplex
> >     multi-speed switch
> > 
> > NFS client:
> > 
> >     vanilla PC
> >     Intel Pro/100 ethernet
> >     Slackware 9.1
> >     Linux kernel 2.6.5, plain with no mods or patches, only enough
> > 	drivers and features enabled to run my workstation
> > 	configuration as close as I could get to my Linux 2.4
> > 	kernel
> 
> This is pretty much covered in the NFS FAQ entry B10.
> 
> You are experiencing the classical effects of using unreliable transport
> (i.e. UDP) on a mixed speed network. Writes to the server are getting
> lost, because it is on a slow segment that cannot keep up with the
> faster 100Mbit clients.

But Charles was seeing good performance with 2.4-based clients.  When he
went to 2.6 everything fell apart.

Do we know why this regression occurred?