On Wed, Mar 30, 2011 at 08:34:24PM +0200, Mark Kettenis wrote:
> > Date: Tue, 29 Mar 2011 22:42:47 +0200
> > From: Claudio Jeker <cje...@diehard.n-r-g.com>
> >
> > Here is a possible fix. The problem was that because of the way NFS uses
> > the socket API it did not turn of the sendbuffer scaling which reset the
> > size of the socket back to 17376 bytes which is a no go when a buffer of
> > more then 17k is generated by NFS. It is better to initialize the sb_wat
> > in soreserve() which is called by NFS and all attach functions.
>
> This no longer does the sbcheckreserve() dance though. Is that alright?
>
The code that was there previously was a bit strange. Since when
sb_hiwat == 0 is true then sb_wat is 0 as well. Additionally
sbcheckreserve() would only cause the watermark to be set to the default
which is tcp_sendspace/tcp_recvspace. So since sb_hiwat == 0 is never run.
--
:wq Claudio
> > Index: netinet/tcp_usrreq.c
> > ===================================================================
> > RCS file: /cvs/src/sys/netinet/tcp_usrreq.c,v
> > retrieving revision 1.105
> > diff -u -p -r1.105 tcp_usrreq.c
> > --- netinet/tcp_usrreq.c 10 Oct 2010 22:02:50 -0000 1.105
> > +++ netinet/tcp_usrreq.c 29 Mar 2011 20:26:55 -0000
> > @@ -653,15 +653,7 @@ tcp_attach(so)
> > int error;
> >
> > if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
> > - /* if low on memory only allow smaller then default buffers */
> > - if (so->so_snd.sb_wat == 0 ||
> > - sbcheckreserve(so->so_snd.sb_wat, tcp_sendspace))
> > - so->so_snd.sb_wat = tcp_sendspace;
> > - if (so->so_rcv.sb_wat == 0 ||
> > - sbcheckreserve(so->so_rcv.sb_wat, tcp_recvspace))
> > - so->so_rcv.sb_wat = tcp_recvspace;
> > -
> > - error = soreserve(so, so->so_snd.sb_wat, so->so_rcv.sb_wat);
> > + error = soreserve(so, tcp_sendspace, tcp_recvspace);
> > if (error)
> > return (error);
> > }
> > Index: kern/uipc_socket2.c
> > ===================================================================
> > RCS file: /cvs/src/sys/kern/uipc_socket2.c,v
> > retrieving revision 1.51
> > diff -u -p -r1.51 uipc_socket2.c
> > --- kern/uipc_socket2.c 24 Sep 2010 02:59:45 -0000 1.51
> > +++ kern/uipc_socket2.c 29 Mar 2011 20:18:46 -0000
> > @@ -353,6 +353,8 @@ soreserve(struct socket *so, u_long sndc
> > goto bad;
> > if (sbreserve(&so->so_rcv, rcvcc))
> > goto bad2;
> > + so->so_snd.sb_wat = sndcc;
> > + so->so_rcv.sb_wat = rcvcc;
> > if (so->so_rcv.sb_lowat == 0)
> > so->so_rcv.sb_lowat = 1;
> > if (so->so_snd.sb_lowat == 0)
