diff --git a/contrib/check-config.py b/contrib/check-config.py
--- a/contrib/check-config.py
+++ b/contrib/check-config.py
@@ -13,6 +13,7 @@ import sys
 
 foundopts = {}
 documented = {}
+allowinconsistent = set()
 
 configre = re.compile(r'''
     # Function call
@@ -36,6 +37,11 @@ configwithre = re.compile('''
 
 configpartialre = (r"""ui\.config""")
 
+ignorere = re.compile(r'''
+    \#\s(?P<reason>internal|experimental|deprecated|developer|inconsistent)\s
+    config:\s(?P<config>\S+\.\S+)$
+    ''', re.VERBOSE | re.MULTILINE)
+
 def main(args):
     for f in args:
         sect = ''
@@ -82,10 +88,12 @@ def main(args):
                 documented[m.group(1)] = 1
 
             # look for ignore markers
-            m = re.search(r'# (?:internal|experimental|deprecated|developer)'
-                          ' config: (\S+\.\S+)$', l)
+            m = ignorere.search(l)
             if m:
-                documented[m.group(1)] = 1
+                if m.group('reason') == 'inconsistent':
+                    allowinconsistent.add(m.group('config'))
+                else:
+                    documented[m.group('config')] = 1
 
             # look for code-like bits
             line = carryover + l
@@ -100,7 +108,8 @@ def main(args):
                     default = ''
                 if re.match('[a-z.]+$', default):
                     default = '<variable>'
-                if name in foundopts and (ctype, default) != foundopts[name]:
+                if (name in foundopts and (ctype, default) != foundopts[name]
+                    and name not in allowinconsistent):
                     print(l)
                     print("conflict on %s: %r != %r" % (name, (ctype, default),
                                                         foundopts[name]))
diff --git a/mercurial/profiling.py b/mercurial/profiling.py
--- a/mercurial/profiling.py
+++ b/mercurial/profiling.py
@@ -141,6 +141,7 @@ def statprofile(ui, fp):
             showmax = ui.configwith(fraction, 'profiling', 'showmax', 0.999)
             kwargs.update(minthreshold=showmin, maxthreshold=showmax)
         elif profformat == 'hotpath':
+            # inconsistent config: profiling.showmin
             limit = ui.configwith(fraction, 'profiling', 'showmin', 0.05)
             kwargs['limit'] = limit
 
diff --git a/tests/test-check-config.t b/tests/test-check-config.t
--- a/tests/test-check-config.t
+++ b/tests/test-check-config.t
@@ -14,6 +14,13 @@ Sanity check check-config.py
   > # Missing with default value
   > foo = ui.configbool('ui', 'missingbool1', default=True)
   > foo = ui.configbool('ui', 'missingbool2', False)
+  > # Inconsistent values for defaults.
+  > foo = ui.configint('ui', 'intdefault', default=1)
+  > foo = ui.configint('ui', 'intdefault', default=42)
+  > # Can suppress inconsistent value error
+  > foo = ui.configint('ui', 'intdefault2', default=1)
+  > # inconsistent config: ui.intdefault2
+  > foo = ui.configint('ui', 'intdefault2', default=42)
   > EOF
 
   $ cat > files << EOF
@@ -24,7 +31,12 @@ Sanity check check-config.py
   $ cd "$TESTDIR"/..
 
   $ $PYTHON contrib/check-config.py < $TESTTMP/files
+  foo = ui.configint('ui', 'intdefault', default=42)
+  
+  conflict on ui.intdefault: ('int', '42') != ('int', '1')
   undocumented: ui.doesnotexist (str)
+  undocumented: ui.intdefault (int) [42]
+  undocumented: ui.intdefault2 (int) [42]
   undocumented: ui.missingbool1 (bool) [True]
   undocumented: ui.missingbool2 (bool)
   undocumented: ui.missingint (int)
@@ -33,6 +45,3 @@ New errors are not allowed. Warnings are
 
   $ syshg files "set:(**.py or **.txt) - tests/**" | sed 's|\\|/|g' |
   >   $PYTHON contrib/check-config.py
-              limit = ui.configwith(fraction, 'profiling', 'showmin', 0.05)
-  
-  conflict on profiling.showmin: ('with', '0.05') != ('with', '0.005')