--- a/mercurial/revlog.py	Fri Jun 23 13:49:34 2017 +0200
+++ b/mercurial/revlog.py	Tue Jul 04 10:17:14 2017 -0400
@@ -282,7 +282,6 @@
         self._nodecache = {nullid: nullrev}
         self._nodepos = None
         self._compengine = 'zlib'
-        self._maxdeltachainspan = -1
 
         v = REVLOG_DEFAULT_VERSION
         opts = getattr(opener, 'options', None)
@@ -301,8 +300,6 @@
             self._lazydeltabase = bool(opts.get('lazydeltabase', False))
             if 'compengine' in opts:
                 self._compengine = opts['compengine']
-            if 'maxdeltachainspan' in opts:
-                self._maxdeltachainspan = opts['maxdeltachainspan']
 
         if self._chunkcachesize <= 0:
             raise RevlogError(_('revlog chunk cache size %r is not greater '
@@ -1599,13 +1596,7 @@
         # - 'compresseddeltalen' is the sum of the total size of deltas we need
         #   to apply -- bounding it limits the amount of CPU we consume.
         dist, l, data, base, chainbase, chainlen, compresseddeltalen = d
-
-        defaultmax = textlen * 4
-        maxdist = self._maxdeltachainspan
-        if not maxdist:
-            maxdist = dist # ensure the conditional pass
-        maxdist = max(maxdist, defaultmax)
-        if (dist > maxdist or l > textlen or
+        if (dist > textlen * 4 or l > textlen or
             compresseddeltalen > textlen * 2 or
             (self._maxchainlen and chainlen > self._maxchainlen)):
             return False