Index: nfs_vfsops.c
===================================================================
RCS file: /scratch/dcvs/src/sys/vfs/nfs/nfs_vfsops.c,v
retrieving revision 1.9
diff -u -r1.9 nfs_vfsops.c
--- nfs_vfsops.c	10 Oct 2003 22:01:13 -0000	1.9
+++ nfs_vfsops.c	24 Oct 2003 11:21:04 -0000
@@ -98,6 +98,14 @@
 SYSCTL_INT(_vfs_nfs, OID_AUTO, debug, CTLFLAG_RW, &nfs_debug, 0, "");
 #endif
 
+/*
+ * Tunable to determine the Read/Write unit size.  Maximum
+ * value is NFS_MAXDATA (default).
+ */
+static int nfs_io_size = NFS_MAXDATA;
+SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs_io_size, CTLFLAG_RW,
+	&nfs_io_size, 0, "NFS optimal I/O unit size");
+
 static int	nfs_iosize (struct nfsmount *nmp);
 static void	nfs_decode_args (struct nfsmount *nmp,
 			struct nfs_args *argp);
@@ -170,7 +178,7 @@
 static void nfs_convert_oargs (struct nfs_args *args,
 				   struct onfs_args *oargs);
 
-static int
+static __inline int
 nfs_iosize(nmp)
 	struct nfsmount* nmp;
 {
@@ -182,8 +190,21 @@
 	 * that it is at least one VM page to avoid wasting buffer
 	 * space.
 	 */
-	iosize = max(nmp->nm_rsize, nmp->nm_wsize);
-	if (iosize < PAGE_SIZE) iosize = PAGE_SIZE;
+
+	/*
+	 * Also make sure that nfs_io_size does not exceeed
+	 * NFS_MAXDATA.  No point having a SYSCTL_PROC() as it
+	 * adds lot of unwanted overhead.
+	 */
+	if (nfs_io_size > NFS_MAXDATA)
+		iosize = NFS_MAXDATA;
+	else
+		iosize = nfs_io_size;
+
+	/* iosize = max(nmp->nm_rsize, nmp->nm_wsize); */
+	if (nfs_io_size < PAGE_SIZE)
+		iosize = PAGE_SIZE;
+
 	return iosize;
 }
 
@@ -283,7 +304,16 @@
 	}
 	nfsm_dissect(sfp, struct nfs_statfs *, NFSX_STATFS(v3));
 	sbp->f_flags = nmp->nm_flag;
-	sbp->f_iosize = nfs_iosize(nmp);
+	
+	if (v3) {
+		if (nmp->nm_sotype == SOCK_STREAM)
+			sbp->f_iosize = nfs_iosize(nmp);
+		else
+			sbp->f_iosize = NFS_MAXDGRAMDATA;
+	} else {
+		sbp->f_iosize = NFS_V2MAXDATA;
+	}
+
 	if (v3) {
 		sbp->f_bsize = NFS_FABLKSIZE;
 		tquad = fxdr_hyper(&sfp->sf_tbytes);
@@ -640,7 +670,7 @@
 		if (argp->sotype == SOCK_DGRAM)
 			maxio = NFS_MAXDGRAMDATA;
 		else
-			maxio = NFS_MAXDATA;
+			maxio = nfs_iosize(nmp); /* SOCK_STREAM case */
 	} else
 		maxio = NFS_V2MAXDATA;
 
@@ -842,7 +872,6 @@
 	struct nfsmount *nmp;
 	struct nfsnode *np;
 	int error;
-	struct vattr attrs;
 
 	if (mp->mnt_flag & MNT_UPDATE) {
 		nmp = VFSTONFS(mp);
@@ -884,8 +913,16 @@
 
 	nmp->nm_timeo = NFS_TIMEO;
 	nmp->nm_retry = NFS_RETRANS;
-	nmp->nm_wsize = NFS_WSIZE;
-	nmp->nm_rsize = NFS_RSIZE;
+	if (argp->flags & NFSMNT_NFSV3) {
+		if (argp->sotype == SOCK_STREAM) {
+			nmp->nm_wsize = nmp->nm_rsize = nfs_iosize(nmp);
+		} else {
+			nmp->nm_wsize = nmp->nm_rsize = NFS_MAXDGRAMDATA;
+		}
+	} else {
+		nmp->nm_wsize = NFS_WSIZE;
+		nmp->nm_rsize = NFS_RSIZE;
+	}
 	nmp->nm_readdirsize = NFS_READDIRSIZE;
 	nmp->nm_numgrps = NFS_MAXGRPS;
 	nmp->nm_readahead = NFS_DEFRAHEAD;
@@ -934,10 +971,16 @@
 	*vpp = NFSTOV(np);
 
 	/*
-	 * Get file attributes for the mountpoint.  This has the side
-	 * effect of filling in (*vpp)->v_type with the correct value.
+	 * Retrieval of mountpoint attributes is delayed until nfs_rot
+	 * or nfs_statfs are first called.  This will happen either when
+	 * we first traverse the mount point or if somebody does a df(1).
+	 *
+	 * NFSSTA_GOTFSINFO is used to flag if we have successfully
+	 * retreived mountpoint attributes.  In the case of NFSv3 we
+	 * also flag static fsinfo.
 	 */
-	VOP_GETATTR(*vpp, &attrs, curthread);
+	if (*vpp != NULL)
+		(*vpp)->v_type = VNON;
 
 	/*
 	 * Lose the lock but keep the ref.
@@ -1033,6 +1076,23 @@
 	if (error)
 		return (error);
 	vp = NFSTOV(np);
+	/*
+	 * Get transfer parameters and root vnode attributes.
+	 */
+	if ((nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
+	    if (nmp->nm_flag & NFSMNT_NFSV3) {
+	        nfs_fsinfo(nmp, vp, curthread);
+		if (nmp->nm_sotype == SOCK_STREAM)
+			mp->mnt_stat.f_iosize = nfs_iosize(nmp);
+		else
+			mp->mnt_stat.f_iosize = NFS_MAXDGRAMDATA;
+	    } else {
+	        struct vattr attrs;
+	        error = VOP_GETATTR(vp, &attrs, curthread);
+		if (!error)
+		    nmp->nm_state |= NFSSTA_GOTFSINFO;		  
+	  }
+	}
 	if (vp->v_type == VNON)
 	    vp->v_type = VDIR;
 	vp->v_flag = VROOT;