[Python-checkins] r46368 - python/trunk/Tools/pybench/pybench.py

[steve.holden]

Author: steve.holden
Date: Fri May 26 19:41:32 2006
New Revision: 46368

Modified:
   python/trunk/Tools/pybench/pybench.py
Log:
Use minimum calibration time rather than avergae to avoid
the illusion of negative run times. Halt with an error if
run times go below 10 ms, indicating that results will be
unreliable.


Modified: python/trunk/Tools/pybench/pybench.py
==============================================================================
--- python/trunk/Tools/pybench/pybench.py	(original)
+++ python/trunk/Tools/pybench/pybench.py	Fri May 26 19:41:32 2006
@@ -126,7 +126,7 @@
         self.operations = self.operations
         self.rounds = self.rounds
 
-    def run(self):
+    def run(self, cruns):
 
         """ Run the test in two phases: first calibrate, then
             do the actual test. Be careful to keep the calibration
@@ -136,20 +136,23 @@
         test = self.test
         calibrate = self.calibrate
         clock = time.clock
-        cruns = self.cruns
         # first calibrate
-        offset = 0.0
+        t = clock()
+        calibrate()
+        offset = clock() - t
         if cruns:
-            for i in range(cruns):
+            for i in range(cruns-1):
                 t = clock()
                 calibrate()
                 t = clock() - t
-                offset = offset + t
-            offset = offset / cruns
+                if t < offset:
+                    offset = t
         # now the real thing
         t = clock()
         test()
         t = clock() - t
+        if t < 0.01:
+            sys.exit("Lower warp required: test times < 10 ms are unreliable")
         self.last_timing = (t-offset,t,offset)
         self.times.append(t-offset)
 
@@ -253,7 +256,7 @@
             print len(l), "tests found"
         print
 
-    def run(self, verbose):
+    def run(self, verbose, cruns):
 
         tests = self.tests.items()
         tests.sort()
@@ -266,10 +269,10 @@
             if verbose:
                 print ' Round %-25i  real   abs    overhead' % (i+1)
             for j in range(len(tests)):
-                name,t = tests[j]
+                name, t = tests[j]
                 if verbose:
                     print '%30s:' % name,
-                t.run()
+                t.run(cruns)
                 if verbose:
                     print '  %.3fr %.3fa %.3fo' % t.last_timing
             if verbose:
@@ -379,7 +382,7 @@
                SwitchOption('--no-syscheck',
                     '"disable" sys check interval (set to sys.maxint)', 0),
                ArgumentOption('-t', 'tests containing substring', ''),
-               ArgumentOption('-C', 'number of calibration runs (default 0)', '')
+               ArgumentOption('-C', 'number of calibration runs (default 20)', 20)
                ]
 
     about = """\
@@ -423,7 +426,9 @@
         limitnames = self.values['-t']
         verbose = self.verbose
         nosyscheck = self.values['--no-syscheck']
-
+        cruns = self.values['-C']
+        print "CRUNS:", cruns
+        
         print 'PYBENCH',__version__
 
         # Switch off GC
@@ -488,7 +493,7 @@
         bench.rounds = rounds
         bench.load_tests(Setup, warp, limitnames, verbose)
         try:
-            bench.run(verbose)
+            bench.run(verbose, cruns)
         except KeyboardInterrupt:
             print
             print '*** KeyboardInterrupt -- Aborting'