inode.c |    9 +++++++++
 1 files changed, 9 insertions(+)

diff -u --recursive --new-file --show-c-function linux-2.6.1-rc2/fs/nfs/inode.c linux-2.6.1-01-fix_setattr/fs/nfs/inode.c
--- linux-2.6.1-rc2/fs/nfs/inode.c	2004-01-07 22:57:48.000000000 -0500
+++ linux-2.6.1-01-fix_setattr/fs/nfs/inode.c	2004-01-08 00:22:49.000000000 -0500
@@ -791,6 +791,8 @@ out_no_inode:
 	goto out;
 }
 
+#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET)
+
 int
 nfs_setattr(struct dentry *dentry, struct iattr *attr)
 {
@@ -798,6 +800,11 @@ nfs_setattr(struct dentry *dentry, struc
 	struct nfs_fattr fattr;
 	int error;
 
+	/* Optimization: if the end result is no change, don't RPC */
+	attr->ia_valid &= NFS_VALID_ATTRS;
+	if (attr->ia_valid == 0)
+		return 0;
+
 	lock_kernel();
 
 	/*
@@ -813,6 +820,8 @@ printk("nfs_setattr: revalidate failed, 
 
 	if (!S_ISREG(inode->i_mode)) {
 		attr->ia_valid &= ~ATTR_SIZE;
+		if (attr->ia_valid == 0)
+			goto out;
 	} else {
 		filemap_fdatawrite(inode->i_mapping);
 		error = nfs_wb_all(inode);