Wed Jun 22 12:25:50 MDT 2011  zooko@zooko.com
  * mathutil: diagnostics about what inputs to next_power_of_k() are causing a NaN-related exception
diff -rN -u old-1.8.2/src/allmydata/util/mathutil.py new-1.8.2/src/allmydata/util/mathutil.py
--- old-1.8.2/src/allmydata/util/mathutil.py	2011-06-22 12:27:25.121490999 -0600
+++ new-1.8.2/src/allmydata/util/mathutil.py	2011-06-22 12:27:25.463490999 -0600
@@ -28,7 +28,7 @@
 def is_power_of_k(n, k):
     return k**int(math.log(n, k) + 0.5) == n
 
-def next_power_of_k(n, k):
+def next_power_of_k_math(n, k):
     if n == 0:
         x = 0
     else:
@@ -38,6 +38,20 @@
     else:
         return k**x
 
+def next_power_of_k_alt(n, k):
+    p = 1
+    while p < n:
+        p *= k
+    return p
+
+def next_power_of_k(n, k):
+    try:
+        return next_power_of_k_math(n, k)
+    except ValueError, e:
+        print "XXX n: %s :: %s, k: %s :: %s, next_power_of_k_alt: %s" % (n, type(n), k, type(k), next_power_of_k_alt(n, k))
+        e.args = tuple(e.args + (n, k, next_power_of_k_alt(n, k)))
+        raise
+
 def ave(l):
     return sum(l) / len(l)