new file mode 100644
--- /dev/null
+++ b/inputs/parameters.yml
@@ -0,0 +1,4 @@
+{base_repository: 'https://hg.mozilla.org/mozilla-central', head_ref: b83235ed0ea5a46e58ee9e6f402171bf908ac25f,
+  head_repository: 'https://hg.mozilla.org/mozilla-central/', head_rev: b83235ed0ea5a46e58ee9e6f402171bf908ac25f,
+  level: '3', message: ' ', optimize_target_tasks: true, owner: cbook@mozilla.com,
+  project: mozilla-central, pushdate: 1470836899, pushlog_id: '30548', target_tasks_method: all_builds_and_tests}

new file mode 100644
--- /dev/null
+++ b/inputs/paramsets.yml
@@ -0,0 +1,326 @@
+full-graph:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+  head_repository: https://hg.mozilla.org/projects/ash/
+  head_rev: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+  level: '1'
+  message: '-b do -p all -u all -t all -j all'
+  optimize_target_tasks: false
+  owner: ryanvm@gmail.com
+  project: try
+  pushdate: 1471830480
+  pushlog_id: '122'
+  target_tasks_method: all
+  legacy_optimize: false
+admiring-ash:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+  head_repository: https://hg.mozilla.org/projects/ash/
+  head_rev: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+  level: '2'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ryanvm@gmail.com
+  project: ash
+  pushdate: 1471830480
+  pushlog_id: '122'
+  target_tasks_method: ash_tasks
+admiring-mozilla-central:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 30fa88c82366a358f412ca2cc3268142c8991f0d
+  head_repository: https://hg.mozilla.org/mozilla-central/
+  head_rev: 30fa88c82366a358f412ca2cc3268142c8991f0d
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: mozilla-central
+  pushdate: 1471653459
+  pushlog_id: '30580'
+  target_tasks_method: default
+awesome-autoland:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 4bfd89efb0c1da0f94b1d580fa7c7f6ce031fcdc
+  head_repository: https://hg.mozilla.org/integration/autoland/
+  head_rev: 4bfd89efb0c1da0f94b1d580fa7c7f6ce031fcdc
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: cpearce@mozilla.com
+  project: autoland
+  pushdate: 1471682286
+  pushlog_id: '31555'
+  target_tasks_method: default
+awesome-mozilla-inbound:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 66d066d5f608c969d486c310d297d2c7fac79aaa
+  head_repository: https://hg.mozilla.org/integration/mozilla-inbound/
+  head_rev: 66d066d5f608c969d486c310d297d2c7fac79aaa
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: spohl@mozilla.com
+  project: mozilla-inbound
+  pushdate: 1471663102
+  pushlog_id: '80846'
+  target_tasks_method: default
+backstabbing-autoland:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: fb9dbacb7f8b52dd47b1ff87f8678179bcf68f4e
+  head_repository: https://hg.mozilla.org/integration/autoland/
+  head_rev: fb9dbacb7f8b52dd47b1ff87f8678179bcf68f4e
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: bchiou@mozilla.com
+  project: autoland
+  pushdate: 1471662396
+  pushlog_id: '31553'
+  target_tasks_method: default
+cocky-autoland:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 258059b7acd8f2ea1448623962a7ca990a2272b6
+  head_repository: https://hg.mozilla.org/integration/autoland/
+  head_rev: 258059b7acd8f2ea1448623962a7ca990a2272b6
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: autoland
+  pushdate: 1471657246
+  pushlog_id: '31552'
+  target_tasks_method: default
+dreamy-mozilla-aurora:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 3443b3c753233c7ea260b09366b4b28ac2c4525a
+  head_repository: https://hg.mozilla.org/releases/mozilla-aurora/
+  head_rev: 3443b3c753233c7ea260b09366b4b28ac2c4525a
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: mozilla-aurora
+  pushdate: 1470869736
+  pushlog_id: '9928'
+  target_tasks_method: default
+drunk-try:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 8035c65525854735f5a5880182a2978414669ce7
+  head_repository: https://hg.mozilla.org/try/
+  head_rev: 8035c65525854735f5a5880182a2978414669ce7
+  level: '1'
+  message: 'try: -b d -p linux -u all -t none'
+  optimize_target_tasks: true
+  owner: leo@gaspard.io
+  project: try
+  pushdate: 1471653704
+  pushlog_id: '140097'
+  target_tasks_method: try_option_syntax
+eager-mozilla-aurora:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 2a0981531355dc77614e72c72fda7498bb074ffe
+  head_repository: https://hg.mozilla.org/releases/mozilla-aurora/
+  head_rev: 2a0981531355dc77614e72c72fda7498bb074ffe
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: mozilla-aurora
+  pushdate: 1470869736
+  pushlog_id: '9927'
+  target_tasks_method: default
+ecstatic-autoland:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 3f3459b7c54ac0225037edc6665113603b85e15c
+  head_repository: https://hg.mozilla.org/integration/autoland/
+  head_rev: 3f3459b7c54ac0225037edc6665113603b85e15c
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ttromey@mozilla.com
+  project: autoland
+  pushdate: 1471720815
+  pushlog_id: '31556'
+  target_tasks_method: default
+elastic-ash:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 7963ebdd52b93f96b812eff2eab8d94097147b9c
+  head_repository: https://hg.mozilla.org/projects/ash/
+  head_rev: 7963ebdd52b93f96b812eff2eab8d94097147b9c
+  level: '2'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ryanvm@gmail.com
+  project: ash
+  pushdate: 1472145383
+  pushlog_id: '126'
+  target_tasks_method: ash_tasks
+elegant-mozilla-central:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 5f3d66a9ea5ddcf59e0b83a81579773aa7d68ae4
+  head_repository: https://hg.mozilla.org/mozilla-central/
+  head_rev: 5f3d66a9ea5ddcf59e0b83a81579773aa7d68ae4
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ryanvm@gmail.com
+  project: mozilla-central
+  pushdate: 1471873097
+  pushlog_id: '30584'
+  target_tasks_method: default
+furious-ash:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 01748a2b1a463f24efd9cd8abad9ccfd76b037b8
+  head_repository: https://hg.mozilla.org/projects/ash/
+  head_rev: 01748a2b1a463f24efd9cd8abad9ccfd76b037b8
+  level: '2'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ryanvm@gmail.com
+  project: ash
+  pushdate: 1472048616
+  pushlog_id: '125'
+  target_tasks_method: ash_tasks
+gigantic-mozilla-central:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+  head_repository: https://hg.mozilla.org/mozilla-central/
+  head_rev: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: mozilla-central
+  pushdate: 1471655785
+  pushlog_id: '30582'
+  target_tasks_method: default
+goofy-mozilla-inbound:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: afd27635d16ebe223b9186f0033b77cd2bbb48d5
+  head_repository: https://hg.mozilla.org/integration/mozilla-inbound/
+  head_rev: afd27635d16ebe223b9186f0033b77cd2bbb48d5
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: mozilla-inbound
+  pushdate: 1471657199
+  pushlog_id: '80844'
+  target_tasks_method: default
+grave-mozilla-inbound:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 7a3c14d1770f8e3f3811642455e144741e9ff67a
+  head_repository: https://hg.mozilla.org/integration/mozilla-inbound/
+  head_rev: 7a3c14d1770f8e3f3811642455e144741e9ff67a
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: jvarga@mozilla.com
+  project: mozilla-inbound
+  pushdate: 1471659416
+  pushlog_id: '80845'
+  target_tasks_method: default
+happy-autoland:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 9de2153ec067c283e5c7fa9732f8742092eddd58
+  head_repository: https://hg.mozilla.org/integration/autoland/
+  head_rev: 9de2153ec067c283e5c7fa9732f8742092eddd58
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: sledru@mozilla.com
+  project: autoland
+  pushdate: 1471681069
+  pushlog_id: '31554'
+  target_tasks_method: default
+loving-mozilla-central:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 662270014cb72f82af415385f2f0bef5b135ec04
+  head_repository: https://hg.mozilla.org/mozilla-central/
+  head_rev: 662270014cb72f82af415385f2f0bef5b135ec04
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ryanvm@gmail.com
+  project: mozilla-central
+  pushdate: 1471872992
+  pushlog_id: '30583'
+  target_tasks_method: default
+peaceful-mozilla-central:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: f0b406c1b36b6b5c881fbb24bc9669d9ef8b9d8a
+  head_repository: https://hg.mozilla.org/mozilla-central/
+  head_rev: f0b406c1b36b6b5c881fbb24bc9669d9ef8b9d8a
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: mozilla-central
+  pushdate: 1471654505
+  pushlog_id: '30581'
+  target_tasks_method: default
+sleepy-ash:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 194fe275b4e60ded2af6b25173eec421f0dba8ad
+  head_repository: https://hg.mozilla.org/projects/ash/
+  head_rev: 194fe275b4e60ded2af6b25173eec421f0dba8ad
+  level: '2'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ryanvm@gmail.com
+  project: ash
+  pushdate: 1471873287
+  pushlog_id: '123'
+  target_tasks_method: ash_tasks
+sleepy-mozilla-inbound:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 59287ede98169ffe2603753658c922b834c2d08a
+  head_repository: https://hg.mozilla.org/integration/mozilla-inbound/
+  head_rev: 59287ede98169ffe2603753658c922b834c2d08a
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: maglione.k@gmail.com
+  project: mozilla-inbound
+  pushdate: 1471652467
+  pushlog_id: '80842'
+  target_tasks_method: default
+stoic-ash:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 052656fc513c05da969590ac5934abd67271a897
+  head_repository: https://hg.mozilla.org/projects/ash/
+  head_rev: 052656fc513c05da969590ac5934abd67271a897
+  level: '2'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ryanvm@gmail.com
+  project: ash
+  pushdate: 1471961311
+  pushlog_id: '124'
+  target_tasks_method: ash_tasks
+tiny-mozilla-aurora:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 7b44f5b3b0bb503b79166ac861b1f3f9c1f8abb9
+  head_repository: https://hg.mozilla.org/releases/mozilla-aurora/
+  head_rev: 7b44f5b3b0bb503b79166ac861b1f3f9c1f8abb9
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: kwierso@gmail.com
+  project: mozilla-aurora
+  pushdate: 1470869736
+  pushlog_id: '9929'
+  target_tasks_method: default
+tiny-mozilla-inbound:
+  base_repository: https://hg.mozilla.org/mozilla-central
+  head_ref: 14733a383b4cf29ce6ed70a5d22dd3cb060c0eb1
+  head_repository: https://hg.mozilla.org/integration/mozilla-inbound/
+  head_rev: 14733a383b4cf29ce6ed70a5d22dd3cb060c0eb1
+  level: '3'
+  message: ' '
+  optimize_target_tasks: true
+  owner: ecoal95@gmail.com
+  project: mozilla-inbound
+  pushdate: 1471656409
+  pushlog_id: '80843'
+  target_tasks_method: default

new file mode 100644
--- /dev/null
+++ b/scripts/compare.py
@@ -0,0 +1,226 @@
+#! /usr/bin/python
+
+"""
+Compare new taskgraphs to old taskgraphs; this uses the data generated by
+gather_old.py (representing the "old" taskgraphs, generated by the legacy kind)
+and calls `mach taskgraph` to create a new taskgraph, then compares the two,
+ignoring unimportant differences and showing any remaining differences, either in the
+tasks created or in the definitions of those tasks.
+"""
+
+import difflib
+import json
+import os
+import re
+import subprocess
+import sys
+
+sys.path.insert(0, 'python/pyyaml/lib')
+import yaml
+
+def relabel(graph):
+    rv = {}
+    for task_id, t in graph.iteritems():
+        l = {}
+        if t['attributes']['kind'] == 'upload-symbols' or t['attributes'].get('post_build') == 'upload-symbols':
+            # no treeherder info, so we make it up
+            l = "US {build_platform}/{build_type}".format(**t['attributes'])
+        elif t['attributes']['kind'] == 'docker-image':
+            # no treeherder info, so we make it up
+            l = "I {image_name}".format(**t['attributes'])
+        else:
+            for name, path, default in [
+                ('gs', 'task.extra.treeherder.groupSymbol', '?'),
+                ('s', 'task.extra.treeherder.symbol', '?'),
+                ('pl', 'task.extra.treeherder.machine.platform', '?'),
+            ]:
+                try:
+                    x = t
+                    for elt in path.split('.'):
+                        x = x[elt]
+                    l[name] = str(x)
+                except KeyError:
+                    l[name] = default
+            try:
+                l['ty'] = '/'.join(sorted(t['task']['extra']['treeherder']['collection'].keys()))
+            except KeyError:
+                l['ty'] = '?'
+            l = '{gs}({s})-{pl}/{ty}'.format(**l)
+        if l in rv:
+            raise Exception("duplicate label %s for %s / %s" % (l, t['label'], rv[l]['label']))
+        rv[l] = t
+    return rv
+
+def replace_labels(graph, str):
+    inverse = {t['task_id']: l for l, t in graph.iteritems()}
+    if not inverse:
+        return str
+    return re.sub("|".join(inverse), lambda mo: inverse[mo.group(0)], str)
+
+def remove(t, path):
+    path = path.split('.')
+    try:
+        for elt in path[:-1]:
+            t = t[elt]
+        del t[path[-1]]
+    except KeyError:
+        pass
+
+def annotate_images(graph):
+    for t in graph.itervalues():
+        # search dependencies for a docker image
+        if 'docker-image' in t['dependencies']:
+            img_task = graph[t['dependencies']['docker-image']]
+            image_name = img_task['attributes']['image_name']
+            t['task']['payload']['docker-image'] = image_name
+    return graph
+
+def drop_stuff(graph):
+    """
+    Drop unimportant aspects of the tasks.
+    """
+    tid2label = {t['task_id']: label for label, t in graph.iteritems()}
+    for t in graph.itervalues():
+        remove(t, 'kind_implementation')
+        remove(t, 'task.created')
+        remove(t, 'task.metadata')
+        remove(t, 'task.deadline')
+        remove(t, 'task.expires')
+        remove(t, 'label')
+        remove(t, 'task.schedulerId')
+        remove(t, 'attributes.kind')
+        remove(t, 'attributes.post_build')
+        remove(t, 'attributes.legacy_kind')
+        remove(t, 'attributes.job')
+        remove(t, 'attributes.e10s')
+        remove(t, 'attributes.run_on_projects')
+
+        # t['dependencies'] is irrelevant in an optimized taskgraph
+        remove(t, 'dependencies')
+
+        # convert dependency taskIds to the target task's label, and sort
+        t['task']['dependencies'] = sorted([tid2label.get(d, 'no-' + d) for d in t['task']['dependencies']])
+
+        if 'env' in t['task']['payload']:
+            env = t['task']['payload']['env']
+            # strip trailing space from configs
+            if 'MOZHARNESS_CONFIG' in env:
+                env['MOZHARNESS_CONFIG'] = env['MOZHARNESS_CONFIG'].rstrip()
+            # treat 'true' and True as the same for env values, fold strings
+            t['task']['payload']['env'] = {v: 'true' if e is True else str(e) for v, e in env.iteritems()}
+
+        # groupName was inconsistent for the same group; fixed now, but ignore the differences
+        remove(t, 'task.extra.treeherder.groupName')
+
+        # ignore groupSymbol == '?'
+        try:
+            if t['task']['extra']['treeherder']['groupSymbol'] == '?':
+                del t['task']['extra']['treeherder']['groupSymbol']
+        except KeyError:
+            pass
+
+        remove(t, 'task.extra.treeherderEnv')
+
+        # this is ignored per
+        # https://schemas.taskcluster.net/taskcluster-treeherder/v1/task-treeherder-config.json#
+        remove(t, 'task.extra.treeherder.build')
+
+        # remove some unused fields; these were leftover variables that snuck
+        # into extra
+        remove(t, 'task.extra.build_name')
+        remove(t, 'task.extra.build_platform')
+        remove(t, 'task.extra.build_product')
+        remove(t, 'task.extra.build_type')
+
+        # unnecessary in new taskgraphs
+        remove(t, 'task.extra.locations')
+
+        # symbols should be strings, even if they are just a chunk number
+        try:
+            t['task']['extra']['treeherder']['symbol'] = str(t['task']['extra']['treeherder']['symbol'])
+        except KeyError:
+            pass
+
+        # sort command options for docker-worker runs, since option order is not consistent
+        if isinstance(t['task']['payload'].get('artifacts'), (dict, type(None))) and 'command' in t['task']['payload']:
+            command = t['task']['payload']['command']
+            command = [s.strip() if isinstance(s, basestring) else s for s in command]
+            t['task']['payload']['command'] = command[:2] + sorted(command[2:])
+
+
+        # make sure that these fields exist, even if empty
+        t['task'].setdefault('scopes', []).sort()
+        t['task'].setdefault('routes', []).sort()
+    return graph
+
+def compare(old, new):
+    graph1 = annotate_images(json.load(open(old)))
+    graph2 = annotate_images(json.load(open(new)))
+
+    graph1 = drop_stuff(relabel(graph1))
+    graph2 = drop_stuff(relabel(graph2))
+
+    print("{} tasks -> {} tasks".format(len(graph1), len(graph2)))
+
+    diff = False
+    show = True
+    ignored = []
+    combined = set(graph1) | set(graph2)
+    for l in sorted(combined):
+        if l in graph1:
+            if l not in graph2:
+                diff = True
+                if show: print("-" + l)
+        else:
+            if l in graph2:
+                # don't count added I tasks as a difference, nor changes to where SM tasks run
+                if l.startswith("I") or 'sm-' in l:
+                    ignored.append(l)
+                else:
+                    diff = True
+                if show: print("+" + l)
+    if diff:
+        return False
+
+    # remove ignored tasks
+    for l in ignored:
+        del graph2[l]
+
+    print "replacing labels"
+    graph1 = replace_labels(graph1, json.dumps(graph1, indent=4, sort_keys=True)).split('\n')
+    graph2 = replace_labels(graph2, json.dumps(graph2, indent=4, sort_keys=True)).split('\n')
+
+    print "calculating diff"
+    for line in difflib.unified_diff(graph1, graph2, fromfile="tasks-old.json", tofile="tasks-new.json", lineterm='', n=20):
+        diff = True
+        print line
+
+    if not diff:
+        print("++++ no diff")
+
+    return not diff
+
+
+def main():
+    force = False
+    verbose = ''
+    if '-f' in sys.argv:
+        sys.argv.remove('-f')
+        force = True
+    if '-v' in sys.argv:
+        sys.argv.remove('-v')
+        verbose = '-v'
+    to_show = set(sys.argv[1:])
+    paramsets = yaml.load(open("inputs/paramsets.yml"))
+    for name, params in paramsets.iteritems():
+        if to_show and name not in to_show:
+            continue
+        print("====== {}".format(name))
+        if force or not os.path.exists("outputs/tasks-new-{}.json".format(name)):
+            with open("parameters.yml", "w") as f:
+                yaml.dump(params, f)
+            subprocess.check_call('./mach taskgraph optimized {} -p parameters.yml -J > outputs/tasks-new-{}.json'.format(verbose, name), shell=True)
+        if not compare("outputs/tasks-old-{}.json".format(name), "outputs/tasks-new-{}.json".format(name)):
+            break
+
+main()

new file mode 100755
--- /dev/null
+++ b/scripts/gather_old.py
@@ -0,0 +1,25 @@
+#! /usr/bin/python
+
+import os
+import sys
+sys.path.insert(0, 'python/pyyaml/lib')
+import subprocess
+
+import yaml
+
+def main():
+    todo = set(sys.argv[1:])
+
+    paramsets = yaml.load(open("inputs/paramsets.yml"))
+    for name, params in paramsets.iteritems():
+        if todo and name not in todo:
+            continue
+        yaml.safe_dump(params, sys.stdout, default_flow_style=False)
+        try:
+            with open("parameters.yml", "w") as f:
+                yaml.dump(params, f)
+            subprocess.check_call('./mach taskgraph optimized -p parameters.yml -J > outputs/tasks-old-{}.json'.format(name), shell=True)
+        finally:
+            os.unlink("parameters.yml")
+
+main()

new file mode 100644
--- /dev/null
+++ b/scripts/get_paramsets.py
@@ -0,0 +1,154 @@
+import sys
+import random
+
+sys.path.insert(0, "python/requests")
+import requests
+sys.path.insert(0, "python/pyyaml/lib")
+import yaml
+
+ADJ = [
+    "admiring",
+    "adoring",
+    "affectionate",
+    "agitated",
+    "amazing",
+    "angry",
+    "awesome",
+    "backstabbing",
+    "berserk",
+    "big",
+    "boring",
+    "clever",
+    "cocky",
+    "compassionate",
+    "condescending",
+    "cranky",
+    "desperate",
+    "determined",
+    "distracted",
+    "dreamy",
+    "drunk",
+    "eager",
+    "ecstatic",
+    "elastic",
+    "elated",
+    "elegant",
+    "evil",
+    "fervent",
+    "focused",
+    "furious",
+    "gigantic",
+    "gloomy",
+    "goofy",
+    "grave",
+    "happy",
+    "high",
+    "hopeful",
+    "hungry",
+    "infallible",
+    "jolly",
+    "jovial",
+    "kickass",
+    "lonely",
+    "loving",
+    "mad",
+    "modest",
+    "naughty",
+    "nauseous",
+    "nostalgic",
+    "peaceful",
+    "pedantic",
+    "pensive",
+    "prickly",
+    "reverent",
+    "romantic",
+    "sad",
+    "serene",
+    "sharp",
+    "sick",
+    "silly",
+    "sleepy",
+    "small",
+    "stoic",
+    "stupefied",
+    "suspicious",
+    "tender",
+    "thirsty",
+    "tiny",
+    "trusting",
+    "zen",
+]
+
+def adjectives():
+    adj = ADJ[:]
+    random.shuffle(adj)
+    for a in adj:
+        yield a
+    for root in adjectives():
+        for a in adj:
+            yield "{}-{}".format(root, a)
+
+## generate a list of decision tasks
+
+headers = {'User-agent': 'Mozilla/5.0'}
+
+paramsets = {}
+
+# create a paramset that will generate the full task graph
+paramsets["full-graph"] = yaml.load("""
+base_repository: https://hg.mozilla.org/mozilla-central
+head_ref: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+head_repository: https://hg.mozilla.org/projects/ash/
+head_rev: f97a056ae6235de7855fd8aaa04fb1c8d183bd06
+level: '1'
+message: '-b do -p all -u all -t all -j all'
+optimize_target_tasks: false
+owner: ryanvm@gmail.com
+project: try
+pushdate: 1471830480
+pushlog_id: '122'
+target_tasks_method: all
+legacy_optimize: false
+""")
+
+continuationToken = None
+for tree, N in [
+        ("try", 1),
+        ("mozilla-aurora", 5),
+        ("mozilla-central", 5),
+        ("ash", 5),
+        ("autoland", 5),
+        ("mozilla-inbound", 5),
+        #('stylo', 5),
+        #('stylo-try', 5),
+    ]:
+    adj_seq = adjectives()
+    def mkname():
+        return "{}-{}".format(adj_seq.next(), tree)
+    url = "https://treeherder.mozilla.org/api/project/{}/jobs/?count={}&job_type_symbol=D&last_modified__gt=2016-08-20T00:00:00".format(tree, N)
+    jobs = requests.get(url, headers=headers).json()['results']
+    for job in jobs:
+        job_guid = job['job_guid']
+        print >>sys.stderr, job_guid, job['last_modified']
+        url = "https://treeherder.mozilla.org/api/jobdetail/?job_guid={}".format(job_guid)
+        things = requests.get(url, headers=headers).json()['results']
+        parameters_url = None
+        for thing in things:
+            if thing['value'] == 'parameters.yml':
+                parameters_url = thing['url']
+                break
+        if parameters_url:
+            parameters = requests.get(parameters_url).text
+            new_param = yaml.load(parameters)
+            if 'level' not in new_param:
+                continue # not real
+            if 'pushdate' not in new_param:
+                new_param['pushdate'] = 1470869736
+            if new_param['target_tasks_method'] == 'all_builds_and_tests':
+                new_param['target_tasks_method'] = 'default'
+            name = mkname()
+            print " ", name
+            paramsets[name] = new_param
+
+with open("inputs/paramsets.yml", "wb") as f:
+    yaml.safe_dump(paramsets, f, default_flow_style=False)

--- a/taskcluster/taskgraph/target_tasks.py
+++ b/taskcluster/taskgraph/target_tasks.py
@@ -24,16 +24,23 @@ def _target_task(name):
     return wrap
 
 
 def get_method(method):
     """Get a target_task_method to pass to a TaskGraphGenerator."""
     return _target_task_methods[method]
 
 
+@_target_task('all')
+def target_tasks_all(full_task_graph, parameters):
+    """Target all tasks.  This can be useful when testing, but is probably
+    not the taskgraph you actually want to run!"""
+    return full_task_graph.tasks.keys()
+
+
 @_target_task('from_parameters')
 def target_tasks_from_parameters(full_task_graph, parameters):
     """Get the target task set from parameters['target_tasks'].  This is
     useful for re-running a decision task with the same target set as in an
     earlier run, by copying `target_tasks.json` into `parameters.yml`."""
     return parameters['target_tasks']
 
 

--- a/taskcluster/taskgraph/task/legacy.py
+++ b/taskcluster/taskgraph/task/legacy.py
@@ -432,16 +432,18 @@ class LegacyTask(base.Task):
             'owner': params['owner'],
             # TODO: Add full mach commands to this example?
             'description': 'Task graph generated via ./mach taskcluster-graph',
             'name': 'task graph local'
         }
 
         # Filter the job graph according to conditions met by this invocation run.
         def should_run(task):
+            if not params.get('legacy_optimize', True):
+                return True
             # Old style build or test task that doesn't define conditions. Always runs.
             if 'when' not in task:
                 return True
 
             when = task['when']
 
             # If the task defines file patterns and we have a set of changed
             # files to compare against, only run if a file pattern matches one