diff --git a/Lib/timeit.py b/Lib/timeit.py
--- a/Lib/timeit.py
+++ b/Lib/timeit.py
@@ -71,8 +71,26 @@ if sys.platform == "win32":
     # On Windows, the best timer is time.clock()
     default_timer = time.clock
 else:
-    # On most other platforms the best timer is time.time()
-    default_timer = time.time
+    # Try to find the most appropriate POSIX clock
+    _clocks = ['CLOCK_PROCESS_CPUTIME_ID', 'CLOCK_MONOTONIC_RAW',
+               'CLOCK_MONOTONIC', 'CLOCK_REALTIME']
+    for _clock in _clocks:
+        try:
+            _clock = getattr(time, _clock)
+        except AttributeError:
+            continue
+        def default_timer():
+            return time.clock_gettime(_clock)
+        try:
+            default_timer()
+        except IOError:
+            # Clock not usuable
+            continue
+        break
+    else:
+        # On most other platforms the best timer is time.time()
+        default_timer = time.time
+    del _clocks
 
 # Don't change the indentation of the template; the reindent() calls
 # in Timer.__init__() depend on setup being indented 4 spaces and stmt