diff --git a/Tools/autotest/check_autotest_speedup.py b/Tools/autotest/check_autotest_speedup.py
new file mode 100755
index 0000000000..a601dcc5e9
--- /dev/null
+++ b/Tools/autotest/check_autotest_speedup.py
@@ -0,0 +1,144 @@
+#!/usr/bin/env python
+
+'''
+Run autotest repeatedly at different speedups to help find best default speedup
+
+AP_FLAKE8_CLEAN
+'''
+
+import optparse
+import os
+import re
+import subprocess
+import time
+
+
+class CheckAutoTestSpeedup(object):
+    def __init__(
+            self,
+            build_target="build.Plane",
+            test_target="test.QuadPlane",
+            min_speedup=1,
+            max_speedup=50,
+            gdb=False,
+            debug=False
+    ):
+        self.build_target = build_target
+        self.test_target = test_target
+        self.min_speedup = min_speedup
+        self.max_speedup = max_speedup
+        self.gdb = gdb
+        self.debug = debug
+
+    def progress(self, message):
+        print("PROGRESS: %s" % (message,))
+
+    def run_program(self, prefix, cmd_list):
+        '''copied in from build_binaries.py'''
+        '''run cmd_list, spewing and setting output in self'''
+        self.progress("Running (%s)" % " ".join(cmd_list))
+        p = subprocess.Popen(cmd_list,
+                             bufsize=1,
+                             stdin=None,
+                             close_fds=True,
+                             stdout=subprocess.PIPE,
+                             stderr=subprocess.STDOUT)
+        self.program_output = ""
+        while True:
+            x = p.stdout.readline()
+            if len(x) == 0:
+                returncode = os.waitpid(p.pid, 0)
+                if returncode:
+                    break
+                    # select not available on Windows... probably...
+                time.sleep(0.1)
+                continue
+            if type(x) == bytes:
+                x = x.decode('utf-8')
+            self.program_output += x
+            x = x.rstrip()
+            print("%s: %s" % (prefix, x))
+        (_, status) = returncode
+        if status != 0:
+            self.progress("Process failed (%s)" %
+                          str(returncode))
+            raise subprocess.CalledProcessError(
+                returncode, cmd_list)
+
+    def run(self):
+        build_args = [
+            "./Tools/autotest/autotest.py",
+            self.build_target
+        ]
+        if opts.debug:
+            build_args.append("--debug")
+        self.run_program("BUILD", build_args)
+        results = {
+        }
+        f = open(os.path.join("/tmp/speedup.txt"), "w")
+        for i in range(self.max_speedup, self.min_speedup-1, -1):
+            self.progress("Checking speedup %u" % i)
+            run_args = [
+                "./Tools/autotest/autotest.py",
+                "--speedup", str(i),
+                "--show-test-timings",
+                self.test_target,
+            ]
+            if opts.gdb:
+                run_args.append("--gdb")
+            self.run_program("SPEEDUP-%03u" % i, run_args)
+            for line in self.program_output.split("\n"):
+                match = re.match(".*tests_total_time.*?([0-9.]+)s.*", line)
+                if match is not None:
+                    break
+            results[i] = float(match.group(1))
+            prog = "%u %f" % (i, results[i])
+            self.progress(prog)
+            print(prog, file=f)
+            f.flush()
+
+        for (speedup, t) in results.items():
+            print("%u %f" % (speedup, t))
+
+
+if __name__ == '__main__':
+    parser = optparse.OptionParser(
+        "check_autotest_speedup.py",
+        epilog=""
+        "e.g. ./Tools/autotest/check_autotest_speedup.py --max-speedup=40 --build-target=build.Sub --test-target=test.Sub"
+    )
+    parser.add_option("--debug",
+                      default=False,
+                      help='compile with debugging')
+    parser.add_option("--gdb",
+                      default=False,
+                      help='run under gdb')
+    parser.add_option("--max-speedup",
+                      type=int,
+                      default=50,
+                      help='max speedup to test')
+    parser.add_option("--min-speedup",
+                      type=int,
+                      default=1,
+                      help='min speedup to test')
+    parser.add_option("--build-target",
+                      type='string',
+                      default='build.Plane',
+                      help='build target (e.g. build.Plane)')
+    parser.add_option("--test-target",
+                      type='string',
+                      default='test.QuadPlane',
+                      help='test target (e.g. test.QuadPlane)')
+
+    opts, args = parser.parse_args()
+
+    checker = CheckAutoTestSpeedup(
+        gdb=opts.gdb,
+        debug=opts.debug,
+        max_speedup=opts.max_speedup,
+        min_speedup=opts.min_speedup,
+        build_target=opts.build_target,
+        test_target=opts.test_target
+    )
+
+    checker.run()