diff --git a/doc/source/admin/components.rst b/doc/source/admin/components.rst
index fbb8cbc..b3a4c3f 100644
--- a/doc/source/admin/components.rst
+++ b/doc/source/admin/components.rst
@@ -115,6 +115,11 @@
       A list of zookeeper hosts for Zuul to use when communicating
       with Nodepool.
 
+   .. attr:: session_timeout
+      :default: 10.0
+
+      The ZooKeeper session timeout, in seconds.
+
 
 .. _scheduler:
 
diff --git a/doc/source/user/jobs.rst b/doc/source/user/jobs.rst
index 3d24f5d..6962b8f 100644
--- a/doc/source/user/jobs.rst
+++ b/doc/source/user/jobs.rst
@@ -244,6 +244,11 @@
          The path to the source code, relative to the work dir.  E.g.,
          `src/git.example.com/org/project`.
 
+      .. var:: required
+
+         A boolean indicating whether this project appears in the
+         :attr:`job.required-projects` list for this job.
+
    .. var:: tenant
 
       The name of the current Zuul tenant.
diff --git a/tests/base.py b/tests/base.py
index df9fbc1..2e3d682 100755
--- a/tests/base.py
+++ b/tests/base.py
@@ -1485,7 +1485,10 @@
             result = super(RecordingAnsibleJob, self).runAnsible(
                 cmd, timeout, playbook)
         else:
-            result = build.run()
+            if playbook.path:
+                result = build.run()
+            else:
+                result = (self.RESULT_NORMAL, 0)
         return result
 
     def getHostList(self, args):
diff --git a/zuul/ansible/filter/zuul_filters.py b/zuul/ansible/filter/zuul_filters.py
index 17ef2bb..eb6776c 100644
--- a/zuul/ansible/filter/zuul_filters.py
+++ b/zuul/ansible/filter/zuul_filters.py
@@ -25,7 +25,8 @@
                   ZUUL_SHORT_PROJECT_NAME=short_name,
                   ZUUL_PIPELINE=zuul['pipeline'],
                   ZUUL_VOTING=zuul['voting'],
-                  WORKSPACE='/home/zuul/workspace')
+                  WORKSPACE='/home/zuul/workspace',
+                  BUILD_TIMEOUT=str(int(zuul['timeout']) * 1000))
     if 'branch' in zuul:
         params['ZUUL_BRANCH'] = zuul['branch']
 
diff --git a/zuul/cmd/migrate.py b/zuul/cmd/migrate.py
index 8688ab4..efb2796 100644
--- a/zuul/cmd/migrate.py
+++ b/zuul/cmd/migrate.py
@@ -932,8 +932,6 @@
         timeout = self.getTimeout()
         if timeout:
             output['timeout'] = timeout
-            output.setdefault('vars', {})
-            output['vars']['BUILD_TIMEOUT'] = str(timeout * 1000)
 
         if self.nodes:
             if len(self.nodes) == 1:
diff --git a/zuul/cmd/scheduler.py b/zuul/cmd/scheduler.py
index a9923c6..bba1922 100755
--- a/zuul/cmd/scheduler.py
+++ b/zuul/cmd/scheduler.py
@@ -154,8 +154,10 @@
         zookeeper = zuul.zk.ZooKeeper()
         zookeeper_hosts = get_default(self.config, 'zookeeper',
                                       'hosts', '127.0.0.1:2181')
+        zookeeper_timeout = float(get_default(self.config, 'zookeeper',
+                                              'session_timeout', 10.0))
 
-        zookeeper.connect(zookeeper_hosts)
+        zookeeper.connect(zookeeper_hosts, timeout=zookeeper_timeout)
 
         cache_expiry = get_default(self.config, 'webapp', 'status_expiry', 1)
         listen_address = get_default(self.config, 'webapp', 'listen_address',
diff --git a/zuul/configloader.py b/zuul/configloader.py
index afdf329..d597ee0 100644
--- a/zuul/configloader.py
+++ b/zuul/configloader.py
@@ -856,9 +856,6 @@
             pipeline_defined = False
             for template in configs:
                 if pipeline.name in template.pipelines:
-                    ProjectParser.log.debug(
-                        "Applying template %s to pipeline %s" %
-                        (template.name, pipeline.name))
                     pipeline_defined = True
                     template_pipeline = template.pipelines[pipeline.name]
                     project_pipeline.job_list.inheritFrom(
diff --git a/zuul/executor/client.py b/zuul/executor/client.py
index f97d286..eb2bfdf 100644
--- a/zuul/executor/client.py
+++ b/zuul/executor/client.py
@@ -234,6 +234,7 @@
         params['vars'] = copy.deepcopy(job.variables)
         params['zuul'] = zuul_params
         projects = set()
+        required_projects = set()
 
         def make_project_dict(project, override_branch=None):
             project_config = item.current_build_set.layout.project_configs.get(
@@ -260,6 +261,7 @@
                     make_project_dict(project,
                                       job_project.override_branch))
                 projects.add(project)
+                required_projects.add(project)
         for i in all_items:
             if i.change.project not in projects:
                 project = i.change.project
@@ -273,6 +275,7 @@
                 canonical_hostname=p.canonical_hostname,
                 canonical_name=p.canonical_name,
                 src_dir=os.path.join('src', p.canonical_name),
+                required=(p in required_projects),
             ))
 
         build = Build(job, uuid)
diff --git a/zuul/executor/server.py b/zuul/executor/server.py
index 27fd85f..b37a82e 100644
--- a/zuul/executor/server.py
+++ b/zuul/executor/server.py
@@ -346,6 +346,15 @@
         self.trusted_projects = []
         self.trusted_project_index = {}
 
+        # Create a JobDirPlaybook for the Ansible setup run.  This
+        # doesn't use an actual playbook, but it lets us use the same
+        # methods to write an ansible.cfg as the rest of the Ansible
+        # runs.
+        setup_root = os.path.join(self.ansible_root, 'setup_playbook')
+        os.makedirs(setup_root)
+        self.setup_playbook = JobDirPlaybook(setup_root)
+        self.setup_playbook.trusted = True
+
     def addTrustedProject(self, canonical_name, branch):
         # Trusted projects are placed in their own directories so that
         # we can support using different branches of the same project
@@ -504,6 +513,21 @@
             super(ExecutorMergeWorker, self).handleNoop(packet)
 
 
+class ExecutorExecuteWorker(gear.TextWorker):
+    def __init__(self, executor_server, *args, **kw):
+        self.zuul_executor_server = executor_server
+        super(ExecutorExecuteWorker, self).__init__(*args, **kw)
+
+    def handleNoop(self, packet):
+        # Delay our response to running a new job based on the number
+        # of jobs we're currently running, in an attempt to spread
+        # load evenly among executors.
+        workers = len(self.zuul_executor_server.job_workers)
+        delay = (workers ** 2) / 1000.0
+        time.sleep(delay)
+        return super(ExecutorExecuteWorker, self).handleNoop(packet)
+
+
 class ExecutorServer(object):
     log = logging.getLogger("zuul.ExecutorServer")
 
@@ -603,7 +627,8 @@
         ssl_ca = get_default(self.config, 'gearman', 'ssl_ca')
         self.merger_worker = ExecutorMergeWorker(self, 'Zuul Executor Merger')
         self.merger_worker.addServer(server, port, ssl_key, ssl_cert, ssl_ca)
-        self.executor_worker = gear.TextWorker('Zuul Executor Server')
+        self.executor_worker = ExecutorExecuteWorker(
+            self, 'Zuul Executor Server')
         self.executor_worker.addServer(server, port, ssl_key, ssl_cert, ssl_ca)
         self.log.debug("Waiting for server")
         self.merger_worker.waitForServer()
@@ -1101,6 +1126,17 @@
     def runPlaybooks(self, args):
         result = None
 
+        # Run the Ansible 'setup' module on all hosts in the inventory
+        # at the start of the job with a 60 second timeout.  If we
+        # aren't able to connect to all the hosts and gather facts
+        # within that timeout, there is likely a network problem
+        # between here and the hosts in the inventory; return them and
+        # reschedule the job.
+        setup_status, setup_code = self.runAnsibleSetup(
+            self.jobdir.setup_playbook)
+        if setup_status != self.RESULT_NORMAL or setup_code != 0:
+            return result
+
         pre_failed = False
         success = False
         for index, playbook in enumerate(self.jobdir.pre_playbooks):
@@ -1213,6 +1249,8 @@
         return None
 
     def preparePlaybooks(self, args):
+        self.writeAnsibleConfig(self.jobdir.setup_playbook)
+
         for playbook in args['pre_playbooks']:
             jobdir_playbook = self.jobdir.addPrePlaybook()
             self.preparePlaybook(jobdir_playbook, playbook,
@@ -1289,7 +1327,7 @@
             jobdir_playbook.secrets_content = yaml.safe_dump(
                 secrets, default_flow_style=False)
 
-        self.writeAnsibleConfig(jobdir_playbook, playbook)
+        self.writeAnsibleConfig(jobdir_playbook)
 
     def checkoutTrustedProject(self, project, branch):
         root = self.jobdir.getTrustedProject(project.canonical_name,
@@ -1420,7 +1458,7 @@
             job_output_file=self.jobdir.job_output_file)
         logging_config.writeJson(self.jobdir.logging_json)
 
-    def writeAnsibleConfig(self, jobdir_playbook, playbook):
+    def writeAnsibleConfig(self, jobdir_playbook):
         trusted = jobdir_playbook.trusted
 
         # TODO(mordred) This should likely be extracted into a more generalized
@@ -1467,7 +1505,7 @@
             # role. Otherwise, printing the args could be useful for
             # debugging.
             config.write('display_args_to_stdout = %s\n' %
-                         str(not playbook['secrets']))
+                         str(not jobdir_playbook.secrets_content))
 
             config.write('[ssh_connection]\n')
             # NB: when setting pipelining = True, keep_remote_files
@@ -1640,6 +1678,21 @@
 
         return (self.RESULT_NORMAL, ret)
 
+    def runAnsibleSetup(self, playbook):
+        if self.executor_server.verbose:
+            verbose = '-vvv'
+        else:
+            verbose = '-v'
+
+        cmd = ['ansible', '*', verbose, '-m', 'setup',
+               '-a', 'gather_subset=!all']
+
+        result, code = self.runAnsible(
+            cmd=cmd, timeout=60, playbook=playbook)
+        self.log.debug("Ansible complete, result %s code %s" % (
+            self.RESULT_MAP[result], code))
+        return result, code
+
     def runAnsiblePlaybook(self, playbook, timeout, success=None,
                            phase=None, index=None):
         if self.executor_server.verbose:
diff --git a/zuul/manager/__init__.py b/zuul/manager/__init__.py
index b94b8a5..2cb34b8 100644
--- a/zuul/manager/__init__.py
+++ b/zuul/manager/__init__.py
@@ -435,12 +435,12 @@
         loader = zuul.configloader.ConfigLoader()
 
         build_set = item.current_build_set
-        self.log.debug("Loading dynamic layout")
         try:
             # First parse the config as it will land with the
             # full set of config and project repos.  This lets us
             # catch syntax errors in config repos even though we won't
             # actually run with that config.
+            self.log.debug("Loading dynamic layout (phase 1)")
             loader.createDynamicLayout(
                 item.pipeline.layout.tenant,
                 build_set.files,
@@ -450,10 +450,12 @@
 
             # Then create the config a second time but without changes
             # to config repos so that we actually use this config.
+            self.log.debug("Loading dynamic layout (phase 2)")
             layout = loader.createDynamicLayout(
                 item.pipeline.layout.tenant,
                 build_set.files,
                 include_config_projects=False)
+            self.log.debug("Loading dynamic layout complete")
         except zuul.configloader.ConfigurationSyntaxError as e:
             self.log.info("Configuration syntax error "
                           "in dynamic layout")
diff --git a/zuul/nodepool.py b/zuul/nodepool.py
index dc855cd..47f5c3c 100644
--- a/zuul/nodepool.py
+++ b/zuul/nodepool.py
@@ -117,7 +117,7 @@
         try:
             for node in nodes:
                 self.log.debug("Locking node %s" % (node,))
-                self.sched.zk.lockNode(node)
+                self.sched.zk.lockNode(node, timeout=30)
                 locked_nodes.append(node)
         except Exception:
             self.log.exception("Error locking nodes:")
diff --git a/zuul/web/__init__.py b/zuul/web/__init__.py
index 00ac9c6..89f5efe 100755
--- a/zuul/web/__init__.py
+++ b/zuul/web/__init__.py
@@ -108,7 +108,7 @@
         except Exception as e:
             self.log.exception("Finger client exception:")
             msg = "Failure from finger client: %s" % e
-            ws.send_str(msg.decode('utf8'))
+            await ws.send_str(msg.decode('utf8'))
 
         return (1000, "No more data")
 
diff --git a/zuul/zk.py b/zuul/zk.py
index 5ea4e56..dcaa172 100644
--- a/zuul/zk.py
+++ b/zuul/zk.py
@@ -90,7 +90,7 @@
     def resetLostFlag(self):
         self._became_lost = False
 
-    def connect(self, hosts, read_only=False):
+    def connect(self, hosts, read_only=False, timeout=10.0):
         '''
         Establish a connection with ZooKeeper cluster.
 
@@ -100,10 +100,12 @@
         :param str hosts: Comma-separated list of hosts to connect to (e.g.
             127.0.0.1:2181,127.0.0.1:2182,[::1]:2183).
         :param bool read_only: If True, establishes a read-only connection.
-
+        :param float timeout: The ZooKeeper session timeout, in
+            seconds (default: 10.0).
         '''
         if self.client is None:
-            self.client = KazooClient(hosts=hosts, read_only=read_only)
+            self.client = KazooClient(hosts=hosts, read_only=read_only,
+                                      timeout=timeout)
             self.client.add_listener(self._connection_listener)
             self.client.start()