zuul/nodepool
Code Issues Proposed changes

Merge "Fix relaunch attempts when hitting quota errors"

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Zuul 2018-07-06 17:41:32 +00:00 committed by Gerrit Code Review
commit 03b7b4baef
7 changed files with 77 additions and 25 deletions
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28
nodepool/driver/__init__.py
View File

@ -300,6 +300,15 @@ class LabelRecorder(object):
self.data.remove({'label': label, 'node_id': node_id})
return node_id
def removeNode(self, id):
'''
Remove the node with the specified ID.
'''
for d in self.data:
if d['node_id'] == id:
self.data.remove(d)
return
class NodeRequestHandlerNotifications(object):
"""
@ -645,9 +654,18 @@ class NodeRequestHandler(NodeRequestHandlerNotifications,
return False
# Launches are complete, so populate ready_nodes and failed_nodes.
for node in self.nodeset:
aborted_nodes = []
for node in self.nodeset[:]:
if node.state == zk.READY:
self.ready_nodes.append(node)
elif node.state == zk.ABORTED:
# ABORTED is a transient error triggered by overquota. In order
# to handle this gracefully don't count this as failed so the
# node is relaunched within this provider. Unlock the node so
# the DeletedNodeWorker cleans up the zNode.
aborted_nodes.append(node)
self.nodeset.remove(node)
self.zk.unlockNode(node)
else:
self.failed_nodes.append(node)
@ -674,6 +692,14 @@ class NodeRequestHandler(NodeRequestHandlerNotifications,
self.log.debug("Declining node request %s because nodes failed",
self.request.id)
self.decline_request()
elif aborted_nodes:
# Because nodes are added to the satisfied types list before they
# are ready we need to remove the aborted nodes again so they can
# be created again.
for node in aborted_nodes:
self._satisfied_types.removeNode(node.id)
self.paused = True
return False
else:
# The assigned nodes must be added to the request in the order
# in which they were requested.

13
nodepool/driver/openstack/handler.py
View File

@ -246,10 +246,12 @@ class OpenStackNodeLauncher(NodeLauncher):
self.zk.storeNode(self.node)
if attempts == self._retries:
raise
# Invalidate the quota cache if we encountered a quota error.
if 'quota exceeded' in str(e).lower():
# A quota exception is not directly recoverable so bail
# out immediately with a specific exception.
self.log.info("Quota exceeded, invalidating quota cache")
self.handler.manager.invalidateQuotaCache()
raise exceptions.QuotaException("Quota exceeded")
attempts += 1
self.node.state = zk.READY
@ -380,8 +382,8 @@ class OpenStackNodeRequestHandler(NodeRequestHandler):
'''
Check if all launch requests have completed.
When all of the Node objects have reached a final state (READY or
FAILED), we'll know all threads have finished the launch process.
When all of the Node objects have reached a final state (READY, FAILED
or ABORTED), we'll know all threads have finished the launch process.
'''
if not self._threads:
return True
@ -392,9 +394,10 @@ class OpenStackNodeRequestHandler(NodeRequestHandler):
node_states = [node.state for node in self.nodeset]
# NOTE: It very important that NodeLauncher always sets one of
# NOTE: It's very important that NodeLauncher always sets one of
# these states, no matter what.
if not all(s in (zk.READY, zk.FAILED) for s in node_states):
if not all(s in (zk.READY, zk.FAILED, zk.ABORTED)
for s in node_states):
return False
return True

11
nodepool/driver/utils.py
View File

@ -22,6 +22,7 @@ import time
from kazoo import exceptions as kze
from nodepool import exceptions
from nodepool import stats
from nodepool import zk
@ -69,6 +70,16 @@ class NodeLauncher(threading.Thread,
self.node.id)
self.node.state = zk.FAILED
statsd_key = 'error.zksession'
except exceptions.QuotaException:
# We encountered a quota error when trying to launch a
# node. In this case we need to abort the launch. The upper
# layers will take care of this and reschedule a new node once
# the quota is ok again.
self.log.info("Aborting node %s due to quota failure" %
self.node.id)
self.node.state = zk.ABORTED
self.zk.storeNode(self.node)
statsd_key = 'error.quota'
except Exception as e:
self.log.exception("Launch failed for node %s:", self.node.id)
self.node.state = zk.FAILED

4
nodepool/exceptions.py
View File

@ -45,6 +45,10 @@ class DibFailedError(BuilderError):
pass
class QuotaException(Exception):
pass
class TimeoutException(Exception):
pass

4
nodepool/launcher.py
View File

@ -224,6 +224,8 @@ class PoolWorker(threading.Thread):
try:
if not r.poll():
active_handlers.append(r)
if r.paused:
self.paused_handler = r
else:
self.log.debug("Removing handler for request %s",
r.request.id)
@ -662,7 +664,7 @@ class DeletedNodeWorker(BaseCleanupWorker):
Delete instances from providers and nodes entries from ZooKeeper.
'''
cleanup_states = (zk.USED, zk.IN_USE, zk.BUILDING, zk.FAILED,
zk.DELETING)
zk.DELETING, zk.ABORTED)
zk_conn = self._nodepool.getZK()
for node in zk_conn.nodeIterator():

37
nodepool/tests/test_launcher.py
View File

@ -297,32 +297,35 @@ class TestLauncher(tests.DBTestCase):
# (according to nodepool's quota estimate) fails.
client.max_instances = 1
# Request a second node; this request should fail.
# Request a second node; this request should pause the handler.
req2 = zk.NodeRequest()
req2.state = zk.REQUESTED
req2.node_types.append('fake-label')
self.log.debug("Adding second request")
self.zk.storeNodeRequest(req2)
req2 = self.waitForNodeRequest(req2)
self.assertEqual(req2.state, zk.FAILED)
# After the second request failed, the internal quota estimate
# should be reset, so the next request should pause to wait
# for more quota to become available.
req3 = zk.NodeRequest()
req3.state = zk.REQUESTED
req3.node_types.append('fake-label')
self.log.debug("Adding third request")
self.zk.storeNodeRequest(req3)
req3 = self.waitForNodeRequest(req3, (zk.PENDING,))
self.assertEqual(req3.state, zk.PENDING)
# Wait until there is a paused request handler and verify that
# there is still only one server built (from the first
# request).
pool_worker = pool.getPoolWorkers('fake-provider')
while not pool_worker[0].paused_handler:
# self.log.debug("tick")
time.sleep(0.1)
self.log.debug("finished waiting")
# The handler is paused now and the request should be in state PENDING
req2 = self.waitForNodeRequest(req2, zk.PENDING)
self.assertEqual(req2.state, zk.PENDING)
# Now free up the first node
self.log.debug("Marking first node as used %s", req1.id)
req1_node.state = zk.USED
self.zk.storeNode(req1_node)
self.zk.unlockNode(req1_node)
self.waitForNodeDeletion(req1_node)
# After the first node is cleaned up the second request should be
# able to fulfill now.
req2 = self.waitForNodeRequest(req2)
self.assertEqual(req2.state, zk.FULFILLED)
self.assertEqual(len(client._server_list), 1)
def test_fail_request_on_launch_failure(self):

5
nodepool/zk.py
View File

@ -52,6 +52,9 @@ USED = 'used'
HOLD = 'hold'
# Initial node state
INIT = 'init'
# Aborted due to a transient error like overquota that should not count as a
# failed launch attempt
ABORTED = 'aborted'
# NOTE(Shrews): Importing this from nodepool.config causes an import error
@ -484,7 +487,7 @@ class Node(BaseModel):
Class representing a launched node.
'''
VALID_STATES = set([BUILDING, TESTING, READY, IN_USE, USED,
HOLD, DELETING, FAILED, INIT])
HOLD, DELETING, FAILED, INIT, ABORTED])
def __init__(self, id=None):
super(Node, self).__init__(id)