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diff --git a/timings/JTimer/SConstruct b/timings/JTimer/SConstruct
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+#
+# __COPYRIGHT__
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+"""
+This configuration is for timing how we evaluate long chains of
+dependencies, specifically when -j is used.
+
+We set up a chain of 100 targets that get built from a Python function
+action with no source files (equivalent to "echo junk > $TARGET").
+Each target explicitly depends on the next target in turn, so the
+Taskmaster will do a deep walk of the dependency graph.
+
+This test case was contributed by Kevin Massey.  Prior to revision 1468,
+we had a serious O(N^2) problem in the Taskmaster when handling long
+dependency chains like this.  That was fixed by adding reference counts
+to the Taskmaster so it could be smarter about not re-evaluating Nodes.
+"""
+
+target_cnt = 100
+
+env = Environment()
+
+def write_file( env, target, source ):
+    path_target = env.File( target ).path
+    outfile = open( path_target, 'w' )
+    outfile.write( 'junk' )
+    outfile.close()
+
+list = []
+for i in range( target_cnt ):
+    target = 'target_%03d' % i
+    env.Command( target, [], write_file )
+    env.Depends( target, list )
+    list.append( target )