diff --git a/tools/perf/tests/attr.py b/tools/perf/tests/attr.py
index e702b82..2f629ca 100644
--- a/tools/perf/tests/attr.py
+++ b/tools/perf/tests/attr.py
@@ -68,7 +68,7 @@
             self[key] = val
 
     def __init__(self, name, data, base):
-        log.info("    Event %s" % name);
+        log.debug("    Event %s" % name);
         self.name  = name;
         self.group = ''
         self.add(base)
@@ -97,6 +97,14 @@
                 return False
         return True
 
+    def diff(self, other):
+        for t in Event.terms:
+            if not self.has_key(t) or not other.has_key(t):
+                continue
+            if not self.compare_data(self[t], other[t]):
+		log.warning("expected %s=%s, got %s" % (t, self[t], other[t]))
+                
+
 # Test file description needs to have following sections:
 # [config]
 #   - just single instance in file
@@ -113,7 +121,7 @@
         parser = ConfigParser.SafeConfigParser()
         parser.read(path)
 
-        log.warning("running '%s'" % path)
+        log.debug("running '%s'" % path)
 
         self.path     = path
         self.test_dir = options.test_dir
@@ -128,7 +136,7 @@
 
         self.expect   = {}
         self.result   = {}
-        log.info("  loading expected events");
+        log.debug("  loading expected events");
         self.load_events(path, self.expect)
 
     def is_event(self, name):
@@ -164,7 +172,7 @@
               self.perf, self.command, tempdir, self.args)
         ret = os.WEXITSTATUS(os.system(cmd))
 
-        log.info("  running '%s' ret %d " % (cmd, ret))
+        log.warning("  running '%s' ret %d " % (cmd, ret))
 
         if ret != int(self.ret):
             raise Unsup(self)
@@ -172,7 +180,7 @@
     def compare(self, expect, result):
         match = {}
 
-        log.info("  compare");
+        log.debug("  compare");
 
         # For each expected event find all matching
         # events in result. Fail if there's not any.
@@ -187,10 +195,11 @@
                 else:
                     log.debug("    ->FAIL");
 
-            log.info("    match: [%s] matches %s" % (exp_name, str(exp_list)))
+            log.debug("    match: [%s] matches %s" % (exp_name, str(exp_list)))
 
             # we did not any matching event - fail
             if (not exp_list):
+		exp_event.diff(res_event)
                 raise Fail(self, 'match failure');
 
             match[exp_name] = exp_list
@@ -208,10 +217,10 @@
                 if res_group not in match[group]:
                     raise Fail(self, 'group failure')
 
-                log.info("    group: [%s] matches group leader %s" %
+                log.debug("    group: [%s] matches group leader %s" %
                          (exp_name, str(match[group])))
 
-        log.info("  matched")
+        log.debug("  matched")
 
     def resolve_groups(self, events):
         for name, event in events.items():
@@ -233,7 +242,7 @@
             self.run_cmd(tempdir);
 
             # load events expectation for the test
-            log.info("  loading result events");
+            log.debug("  loading result events");
             for f in glob.glob(tempdir + '/event*'):
                 self.load_events(f, self.result);