ceph/tasks/cephfs/test_client_recovery.py
John Spray 2b5137bf06 tasks: generalise cephfs test runner
...to avoid having boilerplate in each test module,
and gain the ability to run them all in one go
with a nice test-by-test pass/fail report.

Signed-off-by: John Spray <john.spray@redhat.com>
2015-04-14 14:13:39 +01:00

331 lines
12 KiB
Python

"""
Teuthology task for exercising CephFS client recovery
"""
import logging
import time
from teuthology.orchestra.run import CommandFailedError, ConnectionLostError
from tasks.cephfs.cephfs_test_case import CephFSTestCase
log = logging.getLogger(__name__)
# Arbitrary timeouts for operations involving restarting
# an MDS or waiting for it to come up
MDS_RESTART_GRACE = 60
class TestClientRecovery(CephFSTestCase):
REQUIRE_KCLIENT_REMOTE = True
REQUIRE_ONE_CLIENT_REMOTE = True
CLIENTS_REQUIRED = 2
LOAD_SETTINGS = ["mds_session_timeout", "mds_reconnect_timeout", "ms_max_backoff"]
# Environment references
mds_session_timeout = None
mds_reconnect_timeout = None
ms_max_backoff = None
def test_basic(self):
# Check that two clients come up healthy and see each others' files
# =====================================================
self.mount_a.create_files()
self.mount_a.check_files()
self.mount_a.umount_wait()
self.mount_b.check_files()
self.mount_a.mount()
self.mount_a.wait_until_mounted()
# Check that the admin socket interface is correctly reporting
# two sessions
# =====================================================
ls_data = self._session_list()
self.assert_session_count(2, ls_data)
self.assertSetEqual(
set([l['id'] for l in ls_data]),
{self.mount_a.get_global_id(), self.mount_b.get_global_id()}
)
def test_restart(self):
# Check that after an MDS restart both clients reconnect and continue
# to handle I/O
# =====================================================
self.fs.mds_fail_restart()
self.fs.wait_for_state('up:active', timeout=MDS_RESTART_GRACE)
self.mount_a.create_destroy()
self.mount_b.create_destroy()
def _session_num_caps(self, client_id):
ls_data = self.fs.mds_asok(['session', 'ls'])
return int(self._session_by_id(ls_data).get(client_id, {'num_caps': None})['num_caps'])
def test_reconnect_timeout(self):
# Reconnect timeout
# =================
# Check that if I stop an MDS and a client goes away, the MDS waits
# for the reconnect period
self.fs.mds_stop()
self.fs.mds_fail()
mount_a_client_id = self.mount_a.get_global_id()
self.mount_a.umount_wait(force=True)
self.fs.mds_restart()
self.fs.wait_for_state('up:reconnect', reject='up:active', timeout=MDS_RESTART_GRACE)
ls_data = self._session_list()
self.assert_session_count(2, ls_data)
# The session for the dead client should have the 'reconnect' flag set
self.assertTrue(self.get_session(mount_a_client_id)['reconnecting'])
# Wait for the reconnect state to clear, this should take the
# reconnect timeout period.
in_reconnect_for = self.fs.wait_for_state('up:active', timeout=self.mds_reconnect_timeout * 2)
# Check that the period we waited to enter active is within a factor
# of two of the reconnect timeout.
self.assertGreater(in_reconnect_for, self.mds_reconnect_timeout / 2,
"Should have been in reconnect phase for {0} but only took {1}".format(
self.mds_reconnect_timeout, in_reconnect_for
))
self.assert_session_count(1)
# Check that the client that timed out during reconnect can
# mount again and do I/O
self.mount_a.mount()
self.mount_a.wait_until_mounted()
self.mount_a.create_destroy()
self.assert_session_count(2)
def test_reconnect_eviction(self):
# Eviction during reconnect
# =========================
self.fs.mds_stop()
self.fs.mds_fail()
mount_a_client_id = self.mount_a.get_global_id()
self.mount_a.umount_wait(force=True)
self.fs.mds_restart()
# Enter reconnect phase
self.fs.wait_for_state('up:reconnect', reject='up:active', timeout=MDS_RESTART_GRACE)
self.assert_session_count(2)
# Evict the stuck client
self.fs.mds_asok(['session', 'evict', "%s" % mount_a_client_id])
self.assert_session_count(1)
# Observe that we proceed to active phase without waiting full reconnect timeout
evict_til_active = self.fs.wait_for_state('up:active', timeout=MDS_RESTART_GRACE)
# Once we evict the troublemaker, the reconnect phase should complete
# in well under the reconnect timeout.
self.assertLess(evict_til_active, self.mds_reconnect_timeout * 0.5,
"reconnect did not complete soon enough after eviction, took {0}".format(
evict_til_active
))
# Bring the client back
self.mount_a.mount()
self.mount_a.wait_until_mounted()
self.mount_a.create_destroy()
def test_stale_caps(self):
# Capability release from stale session
# =====================================
cap_holder = self.mount_a.open_background()
# Wait for the file to be visible from another client, indicating
# that mount_a has completed its network ops
self.mount_b.wait_for_visible()
# Simulate client death
self.mount_a.kill()
try:
# Now, after mds_session_timeout seconds, the waiter should
# complete their operation when the MDS marks the holder's
# session stale.
cap_waiter = self.mount_b.write_background()
a = time.time()
cap_waiter.wait()
b = time.time()
# Should have succeeded
self.assertEqual(cap_waiter.exitstatus, 0)
cap_waited = b - a
log.info("cap_waiter waited {0}s".format(cap_waited))
self.assertTrue(self.mds_session_timeout / 2.0 <= cap_waited <= self.mds_session_timeout * 2.0,
"Capability handover took {0}, expected approx {1}".format(
cap_waited, self.mds_session_timeout
))
cap_holder.stdin.close()
try:
cap_holder.wait()
except (CommandFailedError, ConnectionLostError):
# We killed it (and possibly its node), so it raises an error
pass
finally:
# teardown() doesn't quite handle this case cleanly, so help it out
self.mount_a.kill_cleanup()
self.mount_a.mount()
self.mount_a.wait_until_mounted()
def test_evicted_caps(self):
# Eviction while holding a capability
# ===================================
# Take out a write capability on a file on client A,
# and then immediately kill it.
cap_holder = self.mount_a.open_background()
mount_a_client_id = self.mount_a.get_global_id()
# Wait for the file to be visible from another client, indicating
# that mount_a has completed its network ops
self.mount_b.wait_for_visible()
# Simulate client death
self.mount_a.kill()
try:
# The waiter should get stuck waiting for the capability
# held on the MDS by the now-dead client A
cap_waiter = self.mount_b.write_background()
time.sleep(5)
self.assertFalse(cap_waiter.finished)
self.fs.mds_asok(['session', 'evict', "%s" % mount_a_client_id])
# Now, because I evicted the old holder of the capability, it should
# immediately get handed over to the waiter
a = time.time()
cap_waiter.wait()
b = time.time()
cap_waited = b - a
log.info("cap_waiter waited {0}s".format(cap_waited))
# This is the check that it happened 'now' rather than waiting
# for the session timeout
self.assertLess(cap_waited, self.mds_session_timeout / 2.0,
"Capability handover took {0}, expected less than {1}".format(
cap_waited, self.mds_session_timeout / 2.0
))
cap_holder.stdin.close()
try:
cap_holder.wait()
except (CommandFailedError, ConnectionLostError):
# We killed it (and possibly its node), so it raises an error
pass
finally:
self.mount_a.kill_cleanup()
self.mount_a.mount()
self.mount_a.wait_until_mounted()
def test_trim_caps(self):
# Trim capability when reconnecting MDS
# ===================================
count = 500
# Create lots of files
for i in range(count):
self.mount_a.run_shell(["sudo", "touch", "f{0}".format(i)])
# Populate mount_b's cache
self.mount_b.run_shell(["sudo", "ls"])
client_id = self.mount_b.get_global_id()
num_caps = self._session_num_caps(client_id)
self.assertGreaterEqual(num_caps, count)
# Restart MDS. client should trim its cache when reconnecting to the MDS
self.fs.mds_fail_restart()
self.fs.wait_for_state('up:active', timeout=MDS_RESTART_GRACE)
num_caps = self._session_num_caps(client_id)
self.assertLess(num_caps, count,
"should have less than {0} capabilities, have {1}".format(
count, num_caps
))
def test_network_death(self):
"""
Simulate software freeze or temporary network failure.
Check that the client blocks I/O during failure, and completes
I/O after failure.
"""
# We only need one client
self.mount_b.umount_wait()
# Initially our one client session should be visible
client_id = self.mount_a.get_global_id()
ls_data = self._session_list()
self.assert_session_count(1, ls_data)
self.assertEqual(ls_data[0]['id'], client_id)
self.assert_session_state(client_id, "open")
# ...and capable of doing I/O without blocking
self.mount_a.create_files()
# ...but if we turn off the network
self.fs.set_clients_block(True)
# ...and try and start an I/O
write_blocked = self.mount_a.write_background()
# ...then it should block
self.assertFalse(write_blocked.finished)
self.assert_session_state(client_id, "open")
time.sleep(self.mds_session_timeout * 1.5) # Long enough for MDS to consider session stale
self.assertFalse(write_blocked.finished)
self.assert_session_state(client_id, "stale")
# ...until we re-enable I/O
self.fs.set_clients_block(False)
# ...when it should complete promptly
a = time.time()
write_blocked.wait()
b = time.time()
recovery_time = b - a
log.info("recovery time: {0}".format(recovery_time))
self.assertLess(recovery_time, self.ms_max_backoff * 2)
self.assert_session_state(client_id, "open")
def test_filelock(self):
"""
Check that file lock doesn't get lost after an MDS restart
"""
lock_holder = self.mount_a.lock_background()
self.mount_b.wait_for_visible("background_file-2")
self.mount_b.check_filelock()
self.fs.mds_fail_restart()
self.fs.wait_for_state('up:active', timeout=MDS_RESTART_GRACE)
self.mount_b.check_filelock()
# Tear down the background process
lock_holder.stdin.close()
try:
lock_holder.wait()
except (CommandFailedError, ConnectionLostError):
# We killed it, so it raises an error
pass