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Diffstat (limited to 'src/ceph/qa/tasks/mon_thrash.py')
| -rw-r--r-- | src/ceph/qa/tasks/mon_thrash.py | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/src/ceph/qa/tasks/mon_thrash.py b/src/ceph/qa/tasks/mon_thrash.py new file mode 100644 index 0000000..0754bcd --- /dev/null +++ b/src/ceph/qa/tasks/mon_thrash.py @@ -0,0 +1,343 @@ +""" +Monitor thrash +""" +import logging +import contextlib +import ceph_manager +import random +import time +import gevent +import json +import math +from teuthology import misc as teuthology + +log = logging.getLogger(__name__) + +def _get_mons(ctx): + """ + Get monitor names from the context value. + """ + mons = [f[len('mon.'):] for f in teuthology.get_mon_names(ctx)] + return mons + +class MonitorThrasher: + """ + How it works:: + + - pick a monitor + - kill it + - wait for quorum to be formed + - sleep for 'revive_delay' seconds + - revive monitor + - wait for quorum to be formed + - sleep for 'thrash_delay' seconds + + Options:: + + seed Seed to use on the RNG to reproduce a previous + behaviour (default: None; i.e., not set) + revive_delay Number of seconds to wait before reviving + the monitor (default: 10) + thrash_delay Number of seconds to wait in-between + test iterations (default: 0) + thrash_store Thrash monitor store before killing the monitor being thrashed (default: False) + thrash_store_probability Probability of thrashing a monitor's store + (default: 50) + thrash_many Thrash multiple monitors instead of just one. If + 'maintain-quorum' is set to False, then we will + thrash up to as many monitors as there are + available. (default: False) + maintain_quorum Always maintain quorum, taking care on how many + monitors we kill during the thrashing. If we + happen to only have one or two monitors configured, + if this option is set to True, then we won't run + this task as we cannot guarantee maintenance of + quorum. Setting it to false however would allow the + task to run with as many as just one single monitor. + (default: True) + freeze_mon_probability: how often to freeze the mon instead of killing it, + in % (default: 0) + freeze_mon_duration: how many seconds to freeze the mon (default: 15) + scrub Scrub after each iteration (default: True) + + Note: if 'store-thrash' is set to True, then 'maintain-quorum' must also + be set to True. + + For example:: + + tasks: + - ceph: + - mon_thrash: + revive_delay: 20 + thrash_delay: 1 + thrash_store: true + thrash_store_probability: 40 + seed: 31337 + maintain_quorum: true + thrash_many: true + - ceph-fuse: + - workunit: + clients: + all: + - mon/workloadgen.sh + """ + def __init__(self, ctx, manager, config, logger): + self.ctx = ctx + self.manager = manager + self.manager.wait_for_clean() + + self.stopping = False + self.logger = logger + self.config = config + + if self.config is None: + self.config = dict() + + """ Test reproducibility """ + self.random_seed = self.config.get('seed', None) + + if self.random_seed is None: + self.random_seed = int(time.time()) + + self.rng = random.Random() + self.rng.seed(int(self.random_seed)) + + """ Monitor thrashing """ + self.revive_delay = float(self.config.get('revive_delay', 10.0)) + self.thrash_delay = float(self.config.get('thrash_delay', 0.0)) + + self.thrash_many = self.config.get('thrash_many', False) + self.maintain_quorum = self.config.get('maintain_quorum', True) + + self.scrub = self.config.get('scrub', True) + + self.freeze_mon_probability = float(self.config.get('freeze_mon_probability', 10)) + self.freeze_mon_duration = float(self.config.get('freeze_mon_duration', 15.0)) + + assert self.max_killable() > 0, \ + 'Unable to kill at least one monitor with the current config.' + + """ Store thrashing """ + self.store_thrash = self.config.get('store_thrash', False) + self.store_thrash_probability = int( + self.config.get('store_thrash_probability', 50)) + if self.store_thrash: + assert self.store_thrash_probability > 0, \ + 'store_thrash is set, probability must be > 0' + assert self.maintain_quorum, \ + 'store_thrash = true must imply maintain_quorum = true' + + self.thread = gevent.spawn(self.do_thrash) + + def log(self, x): + """ + locally log info messages + """ + self.logger.info(x) + + def do_join(self): + """ + Break out of this processes thrashing loop. + """ + self.stopping = True + self.thread.get() + + def should_thrash_store(self): + """ + If allowed, indicate that we should thrash a certain percentage of + the time as determined by the store_thrash_probability value. + """ + if not self.store_thrash: + return False + return self.rng.randrange(0, 101) < self.store_thrash_probability + + def thrash_store(self, mon): + """ + Thrash the monitor specified. + :param mon: monitor to thrash + """ + addr = self.ctx.ceph['ceph'].conf['mon.%s' % mon]['mon addr'] + self.log('thrashing mon.{id}@{addr} store'.format(id=mon, addr=addr)) + out = self.manager.raw_cluster_cmd('-m', addr, 'sync', 'force') + j = json.loads(out) + assert j['ret'] == 0, \ + 'error forcing store sync on mon.{id}:\n{ret}'.format( + id=mon,ret=out) + + def should_freeze_mon(self): + """ + Indicate that we should freeze a certain percentago of the time + as determined by the freeze_mon_probability value. + """ + return self.rng.randrange(0, 101) < self.freeze_mon_probability + + def freeze_mon(self, mon): + """ + Send STOP signal to freeze the monitor. + """ + log.info('Sending STOP to mon %s', mon) + self.manager.signal_mon(mon, 19) # STOP + + def unfreeze_mon(self, mon): + """ + Send CONT signal to unfreeze the monitor. + """ + log.info('Sending CONT to mon %s', mon) + self.manager.signal_mon(mon, 18) # CONT + + def kill_mon(self, mon): + """ + Kill the monitor specified + """ + self.log('killing mon.{id}'.format(id=mon)) + self.manager.kill_mon(mon) + + def revive_mon(self, mon): + """ + Revive the monitor specified + """ + self.log('killing mon.{id}'.format(id=mon)) + self.log('reviving mon.{id}'.format(id=mon)) + self.manager.revive_mon(mon) + + def max_killable(self): + """ + Return the maximum number of monitors we can kill. + """ + m = len(_get_mons(self.ctx)) + if self.maintain_quorum: + return max(math.ceil(m/2.0)-1, 0) + else: + return m + + def do_thrash(self): + """ + Cotinuously loop and thrash the monitors. + """ + self.log('start thrashing') + self.log('seed: {s}, revive delay: {r}, thrash delay: {t} '\ + 'thrash many: {tm}, maintain quorum: {mq} '\ + 'store thrash: {st}, probability: {stp} '\ + 'freeze mon: prob {fp} duration {fd}'.format( + s=self.random_seed,r=self.revive_delay,t=self.thrash_delay, + tm=self.thrash_many, mq=self.maintain_quorum, + st=self.store_thrash,stp=self.store_thrash_probability, + fp=self.freeze_mon_probability,fd=self.freeze_mon_duration, + )) + + while not self.stopping: + mons = _get_mons(self.ctx) + self.manager.wait_for_mon_quorum_size(len(mons)) + self.log('making sure all monitors are in the quorum') + for m in mons: + s = self.manager.get_mon_status(m) + assert s['state'] == 'leader' or s['state'] == 'peon' + assert len(s['quorum']) == len(mons) + + kill_up_to = self.rng.randrange(1, self.max_killable()+1) + mons_to_kill = self.rng.sample(mons, kill_up_to) + self.log('monitors to thrash: {m}'.format(m=mons_to_kill)) + + mons_to_freeze = [] + for mon in mons: + if mon in mons_to_kill: + continue + if self.should_freeze_mon(): + mons_to_freeze.append(mon) + self.log('monitors to freeze: {m}'.format(m=mons_to_freeze)) + + for mon in mons_to_kill: + self.log('thrashing mon.{m}'.format(m=mon)) + + """ we only thrash stores if we are maintaining quorum """ + if self.should_thrash_store() and self.maintain_quorum: + self.thrash_store(mon) + + self.kill_mon(mon) + + if mons_to_freeze: + for mon in mons_to_freeze: + self.freeze_mon(mon) + self.log('waiting for {delay} secs to unfreeze mons'.format( + delay=self.freeze_mon_duration)) + time.sleep(self.freeze_mon_duration) + for mon in mons_to_freeze: + self.unfreeze_mon(mon) + + if self.maintain_quorum: + self.manager.wait_for_mon_quorum_size(len(mons)-len(mons_to_kill)) + for m in mons: + if m in mons_to_kill: + continue + s = self.manager.get_mon_status(m) + assert s['state'] == 'leader' or s['state'] == 'peon' + assert len(s['quorum']) == len(mons)-len(mons_to_kill) + + self.log('waiting for {delay} secs before reviving monitors'.format( + delay=self.revive_delay)) + time.sleep(self.revive_delay) + + for mon in mons_to_kill: + self.revive_mon(mon) + # do more freezes + if mons_to_freeze: + for mon in mons_to_freeze: + self.freeze_mon(mon) + self.log('waiting for {delay} secs to unfreeze mons'.format( + delay=self.freeze_mon_duration)) + time.sleep(self.freeze_mon_duration) + for mon in mons_to_freeze: + self.unfreeze_mon(mon) + + self.manager.wait_for_mon_quorum_size(len(mons)) + for m in mons: + s = self.manager.get_mon_status(m) + assert s['state'] == 'leader' or s['state'] == 'peon' + assert len(s['quorum']) == len(mons) + + if self.scrub: + self.log('triggering scrub') + try: + self.manager.raw_cluster_cmd('scrub') + except Exception: + log.exception("Saw exception while triggering scrub") + + if self.thrash_delay > 0.0: + self.log('waiting for {delay} secs before continuing thrashing'.format( + delay=self.thrash_delay)) + time.sleep(self.thrash_delay) + +@contextlib.contextmanager +def task(ctx, config): + """ + Stress test the monitor by thrashing them while another task/workunit + is running. + + Please refer to MonitorThrasher class for further information on the + available options. + """ + if config is None: + config = {} + assert isinstance(config, dict), \ + 'mon_thrash task only accepts a dict for configuration' + assert len(_get_mons(ctx)) > 2, \ + 'mon_thrash task requires at least 3 monitors' + log.info('Beginning mon_thrash...') + first_mon = teuthology.get_first_mon(ctx, config) + (mon,) = ctx.cluster.only(first_mon).remotes.iterkeys() + manager = ceph_manager.CephManager( + mon, + ctx=ctx, + logger=log.getChild('ceph_manager'), + ) + thrash_proc = MonitorThrasher(ctx, + manager, config, + logger=log.getChild('mon_thrasher')) + try: + log.debug('Yielding') + yield + finally: + log.info('joining mon_thrasher') + thrash_proc.do_join() + mons = _get_mons(ctx) + manager.wait_for_mon_quorum_size(len(mons)) |