diff --git a/mercurial/lsprof.py b/mercurial/lsprof.py
--- a/mercurial/lsprof.py
+++ b/mercurial/lsprof.py
@@ -48,7 +48,7 @@
         d = self.data
         if top is not None:
             d = d[:top]
-        cols = "% 12s %12s %11.4f %11.4f   %s\n"
+        cols = "% 12d %12d %11.4f %11.4f   %s\n"
         hcols = "% 12s %12s %12s %12s %s\n"
         file.write(hcols % ("CallCount", "Recursive", "Total(s)",
                             "Inline(s)", "module:lineno(function)"))