diff -r 307de98f49ab -r bfac87aa5771 src/python/m5/stats/__init__.py
--- a/src/python/m5/stats/__init__.py	Wed Apr 24 11:25:38 2013 +0100
+++ b/src/python/m5/stats/__init__.py	Wed Apr 24 11:26:04 2013 +0100
@@ -253,6 +253,9 @@
         shelf['info%d' % stat.id] = stat._info
         shelf['value%d' % stat.id] = stat.value
 
+## @brief Keeps track of the number of stats dumps which have occured.
+dumpCount = 0
+
 class display_text(object):
     def __init__(self, filename, desc):
         self.filename = filename
@@ -270,8 +273,13 @@
         save_desc = display.descriptions
         display.descriptions = self.desc
 
-        # Open the input file.
-        f = m5.core.openOutputFile(self.filename, 'a')
+        # Open the input file. Check to see if this is the first time
+        # that we are opening it during this run of gem5. Either
+        # overwrite it if it already exists and we are writing the
+        # stats for the first time, or append to the file if this is
+        # not the first stats dump.
+        mode = 'w' if dumpCount == 0 else 'a'
+        f = m5.core.openOutputFile(self.filename, mode)
 
         print >>f
         print >>f, "---------- Begin Simulation Statistics ----------"
@@ -313,6 +321,11 @@
     for output in outputList:
         output(context)
 
+    # Increment dumpCount to keep track of the number of dumps which
+    # have occured.
+    global dumpCount
+    dumpCount += 1
+
 ## @brief Reset all statistics to the base state.
 def reset():
     # call reset stats on all SimObjects
diff -r 307de98f49ab -r bfac87aa5771 src/python/m5/stats/display.py
--- a/src/python/m5/stats/display.py	Wed Apr 24 11:25:38 2013 +0100
+++ b/src/python/m5/stats/display.py	Wed Apr 24 11:26:04 2013 +0100
@@ -171,7 +171,10 @@
             p.display(out)
             return
 
-        mytotal = reduce(lambda x,y: float(x) + float(y), self.value)
+        mytotal = sum( x for x in self.value if not isnan(x) )
+        if isnan(mytotal):
+            mytotal = 0
+
         mycdf = 0.0
 
         value = self.value
@@ -378,12 +381,12 @@
     if any(stat.subnames):
         subnames = stat.subnames
     else:
-        subnames = range(stat.x)
+        subnames = map(str, range(stat.x))
 
     if any(stat.y_subnames):
         y_subnames = stat.y_subnames
     else:
-        y_subnames = range(stat.y)
+        y_subnames = map(str, range(stat.y))
 
     for x,sname in enumerate(subnames):
         o = x * stat.y
diff -r 307de98f49ab -r bfac87aa5771 src/python/m5/stats/info.py
--- a/src/python/m5/stats/info.py	Wed Apr 24 11:25:38 2013 +0100
+++ b/src/python/m5/stats/info.py	Wed Apr 24 11:26:04 2013 +0100
@@ -91,7 +91,11 @@
 ## @brief Sum all of the values for a stat.
 # @return The sum.
 def total(stat):
-    return sum(values(stat))
+    val = values(stat)
+    try:
+        return sum(val)
+    except TypeError:
+        return val
 
 ## @brief Get the length of a stat.
 # @return The length.
@@ -103,7 +107,7 @@
 # the value. These are used to calculate combinations of statistics.
 class Value(object):
     def __getattr__(self, attr):
-        if attr in ('__scalar__', '__vector'):
+        if attr in ('__scalar__', '__vector__'):
             raise AttributeError, "must define %s for %s" % (attr, type (self))
 
         raise AttributeError, \
@@ -149,6 +153,11 @@
     def __scalar__(self):
         return True
 
+    ## @brief Get the length of the stat.
+    # @return 1 as the length of a scalar is always 1.
+    def __len__(self):
+        return 1
+
     ## @brief Test if a stat is a vector.
     # @return False
     def __vector__(self):
@@ -213,6 +222,11 @@
     def __value__(self):
         return self.constant
 
+    ## @brief Get the length of the stat.
+    # @return 1 as the length of a scalar is always 1.
+    def __len__(self):
+        return 1
+
     ## @brief Get the constant as a string.
     # @return A string representation of the constant.
     def __str__(self):
@@ -859,7 +873,7 @@
         if not other:
             return self
         if isinstance(self.value, (list, tuple)):
-            for iq in xrange(len(self.value)):
+            for i in xrange(len(self.value)):
                 self.value[i] /= other
         else:
             self.value /= other