diff -r d6beeb618700 -r a7527c5769bb mercurial/fileset.py
--- a/mercurial/fileset.py	Sat Aug 08 18:52:59 2015 -0700
+++ b/mercurial/fileset.py	Mon Aug 10 15:30:28 2015 -0500
@@ -295,7 +295,7 @@
 
 def _sizetomax(s):
     try:
-        s = s.strip()
+        s = s.strip().lower()
         for k, v in util._sizeunits:
             if s.endswith(k):
                 # max(4k) = 5k - 1, max(4.5k) = 4.6k - 1