diff --git a/tests/cstore-datapackstore.py b/tests/cstore-datapackstore.py
--- a/tests/cstore-datapackstore.py
+++ b/tests/cstore-datapackstore.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python2.7
 
+import copy
 import hashlib
 import os
 import random
@@ -11,6 +12,7 @@
 
 import silenttestrunner
 
+from timeit import default_timer as timer
 # Load the local cstore, not the system one
 fullpath = os.path.join(os.getcwd(), __file__)
 sys.path.insert(0, os.path.dirname(os.path.dirname(fullpath)))
@@ -20,6 +22,7 @@
 )
 
 from remotefilelog.datapack import (
+    datapackstore as correctstore,
     fastdatapack,
     mutabledatapack,
 )
@@ -59,6 +62,45 @@
         path = packer.close()
         return fastdatapack(path)
 
+    def testGetDeltaChainPerf(self):
+        """Test the performance of fetching the delta chain."""
+        packdir = self.makeTempDir()
+        numfiles = 200
+        numlines = 100
+        revisions = []
+
+        for i in range(numfiles):
+            revisionlist = []
+            revision = (str(i), self.getFakeHash(), nullid, "content")
+
+            for j in range(numlines):
+                revisionlist.append(revision)
+                revision = (
+                    str(i),
+                    self.getFakeHash(),
+                    revision[1],
+                    self.getFakeHash()
+                )
+
+            self.createPack(packdir, revisions=revisionlist)
+            revisions.append(revisionlist)
+
+        store = correctstore(mercurial.ui.ui(), packdir, True)
+
+        totaltime = 0
+        random.shuffle(revisions)
+        for l in revisions:
+            oldlist = copy.deepcopy(l)
+            random.shuffle(l)
+            for r in l:
+                start = timer()
+                chain = store.getdeltachain(r[0], r[1])
+                totaltime += timer() - start
+                self.assertEquals(oldlist.index(r) + 1, len(chain))
+
+        sys.stdout.write('%s seconds\n' % str(totaltime))
+        sys.stdout.flush()
+
     def testGetDeltaChainSingleRev(self):
         """Test getting a 1-length delta chain."""
         packdir = self.makeTempDir()