diff --git a/actions/twittersettings.php b/actions/twittersettings.php
index 45725d3ff4..0b98eef591 100644
--- a/actions/twittersettings.php
+++ b/actions/twittersettings.php
@@ -261,7 +261,7 @@ class TwittersettingsAction extends ConnectSettingsAction
                                             'alt' =>  ($other->fullname) ?
                                             $other->fullname :
                                             $other->nickname));
-                
+
                 $this->element('span', 'fn nickname', $other->nickname);
                 $this->elementEnd('a');
                 $this->elementEnd('li');
@@ -375,6 +375,8 @@ class TwittersettingsAction extends ConnectSettingsAction
 
         if ($friendsync) {
             save_twitter_friends($user, $twit_user->id, $screen_name, $password);
+            $flink->last_friendsync = common_sql_now();
+            $flink->update();
         }
 
         $this->showForm(_('Twitter settings saved.'), true);
diff --git a/scripts/synctwitterfriends.php b/scripts/synctwitterfriends.php
index 794301f0f0..bd08ba58d6 100755
--- a/scripts/synctwitterfriends.php
+++ b/scripts/synctwitterfriends.php
@@ -32,8 +32,25 @@ define('LACONICA', true);
 
 require_once(INSTALLDIR . '/lib/common.php');
 
+// Make a lockfile
+$lockfilename = lockFilename();
+if (!($lockfile = @fopen($lockfilename, "w"))) {
+    print "Already running... exiting.\n";
+    exit(1);
+}
+
+// Obtain an exlcusive lock on file (will fail if script is already going)
+if (!@flock( $lockfile, LOCK_EX | LOCK_NB, &$wouldblock) || $wouldblock) {
+    // Script already running - abort
+    @fclose($lockfile);
+    print "Already running... exiting.\n";
+    exit(1);
+}
+
 $flink = new Foreign_link();
 $flink->service = 1; // Twitter
+$flink->orderBy('last_friendsync');
+$flink->limit(25);  // sync this many users during this run
 $cnt = $flink->find();
 
 print "Updating Twitter friends subscriptions for $cnt users.\n";
@@ -60,8 +77,11 @@ while ($flink->fetch()) {
             continue;
         }
 
-        $result = save_twitter_friends($user, $fuser->id,
-                       $fuser->nickname, $flink->credentials);
+        save_twitter_friends($user, $fuser->id, $fuser->nickname, $flink->credentials);
+
+        $flink->last_friendsync = common_sql_now();
+        $flink->update();
+
         if (defined('SCRIPT_DEBUG')) {
             print "\nDONE\n";
         } else {
@@ -70,4 +90,18 @@ while ($flink->fetch()) {
     }
 }
 
+function lockFilename()
+{
+    $piddir = common_config('daemon', 'piddir');
+    if (!$piddir) {
+        $piddir = '/var/run';
+    }
+
+    return $piddir . '/synctwitterfriends.lock';
+}
+
+// Cleanup
+fclose($lockfile);
+unlink($lockfilename);
+
 exit(0);