NFS on ZFS pure SSD pool

[Sam Fourman Jr.]

On Sun, Sep 1, 2013 at 2:16 PM, Mikolaj Golub <trociny at freebsd.org> wrote:

> On Fri, Aug 30, 2013 at 07:28:44PM -0400, Rick Macklem wrote:
> > Sam Fourman Jr. wrote:
> > > $ cat /var/log/messages | grep failed
> > > Aug 30 10:22:20 students nfsd[1978]: accept failed: Software caused
> > > connection abort
> > > Aug 30 10:27:16 students nfsd[1978]: accept failed: Software caused
> > > connection abort
> > > Aug 30 11:46:30 students nfsd[1978]: accept failed: Software caused
> > > connection abort
> > > Aug 30 11:47:10 students nfsd[1978]: accept failed: Software caused
> > > connection abort
> > >
> > Since the master socket that is accepting connections isn't being closed,
> > I believe this error (ECONNABORTED returned by accept()) occurs when the
> > client closes the new TCP connection before it has been accepted. Why
> > would an NFS client do this? I have no idea.
>
> May be because nfsd is too slow accepting new connections and the
> client aborts due to its timeout? May nfssvc(2) block for some
> considerable time?
>
> Sam, you could monitor nfsd listen queue running netstat -nL
> periodically and current client connections to nfsd with netstat -na,
> to see what is going on. Also enabling ktrace on the nfsd process when
> the issue is observed could tell if it is due to nfssvc(2) is slow.
>
> BTW, I noticed that nfsd sets listen backlog to 5. Isn't it a bit low
> for servers that might have hundreds clients?
>

is there a sysctl to increase the listen backlog for nfsd?

>
> --
> Mikolaj Golub
>



-- 

Sam Fourman Jr.