Branch b1_6

Don't run filter_grant_sanity_check for more than 100 exports
to improve scaling for large numbers of clients.

b=10291
i=wangdi
i=adilger

lustre/ChangeLog

@@ -21,6 +21,12 @@ Description: Transient SCSI error results in persistent IO issue
 Details    : iobuf->dr_error is not reinitialized to 0 between two
 	     uses.
 
+Severity   : minor
+Bugzilla   : 12364
+Description: poor connect scaling with increasing client count
+Details    : Don't run filter_grant_sanity_check for more than 100 exports
+	     to improve scaling for large numbers of clients.
+
 Severity   : normal
 Frequency  : SLES10 only
 Bugzilla   : 12538

lustre/obdfilter/filter.c

@@ -2093,6 +2093,11 @@ static void filter_grant_sanity_check(struct obd_device *obd, const char *func)
         if (list_empty(&obd->obd_exports))
                 return;
 
+        /* We don't want to do this for large machines that do lots of
+           mounts or unmounts.  It burns... */
+        if (obd->obd_num_exports > 100)
+                return;
+
         spin_lock(&obd->obd_osfs_lock);
         spin_lock(&obd->obd_dev_lock);
         list_for_each_entry(exp, &obd->obd_exports, exp_obd_chain) {