""" Monitor thrash """ import logging import contextlib import random import time import gevent import json import math from gevent.event import Event from teuthology import misc as teuthology from teuthology.contextutil import safe_while from tasks import ceph_manager from tasks.cephfs.filesystem import MDSCluster from tasks.thrasher import Thrasher 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(Thrasher): """ 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) switch_thrashers: Toggle this to switch between thrashers so it waits until all thrashers are done thrashing before proceeding. And then wait until all thrashers are done reviving before proceeding. (default: false) store_thrash Thrash monitor store before killing the monitor being thrashed (default: False) store_thrash_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) check_mds_failover Check if mds failover happened (default: False) 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 store_thrash: true store_thrash_probability: 40 seed: 31337 maintain_quorum: true thrash_many: true check_mds_failover: True - ceph-fuse: - workunit: clients: all: - mon/workloadgen.sh """ def __init__(self, ctx, manager, config, name, logger): super(MonitorThrasher, self).__init__() self.ctx = ctx self.manager = manager self.manager.wait_for_clean() self.stopping = Event() self.logger = logger self.config = config self.name = name if self.config is None: self.config = dict() if self.config.get("switch_thrashers"): self.switch_thrasher = Event() """ 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' #MDS failover self.mds_failover = self.config.get('check_mds_failover', False) if self.mds_failover: self.mds_cluster = MDSCluster(ctx) self.thread = gevent.spawn(self.do_thrash) def log(self, x): """ locally log info messages """ self.logger.info(x) def stop(self): """ Stop the thrashing process. """ self.stopping.set() def join(self): """ Break out of this processes thrashing loop. """ self.stopping.set() self.thread.get() def stop_and_join(self): """ Stop the thrashing process and join the thread. """ self.stop() return self.join() 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 """ self.log('thrashing mon.{id} store'.format(id=mon)) out = self.manager.raw_cluster_cmd( 'tell', 'mon.%s' % mon, 'sync_force', '--yes-i-really-mean-it') 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('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 _wait_until_quorum(self, mon, size, timeout=300): """ Wait until the monitor specified is in the quorum. """ self.log('waiting for quorum size %d for mon %s' % (size, mon)) s = {} with safe_while(sleep=3, tries=timeout // 3, action=f'wait for quorum size {size} on mon {mon}') as proceed: while proceed(): s = self.manager.get_mon_status(mon) if len(s['quorum']) == size: break self.log("quorum is size %d" % len(s['quorum'])) self.log("final quorum is size %d" % len(s['quorum'])) return s def do_thrash(self): """ _do_thrash() wrapper. """ try: self._do_thrash() except Exception as e: # See _run exception comment for MDSThrasher self.set_thrasher_exception(e) self.logger.exception("exception:") # Allow successful completion so gevent doesn't see an exception. # The DaemonWatchdog will observe the error and tear down the test. def switch_task(self): """ Pause mon thrasher till other thrashers are done with their iteration. This would help to sync between multiple thrashers, like: 1. thrasher-1 and thrasher-2: thrash daemons in parallel 2. thrasher-1 and thrasher-2: revive daemons in parallel This allows us to run some checks after each thrashing and reviving iteration. """ if not hasattr(self, 'switch_thrasher'): return self.switch_thrasher.set() thrashers = self.ctx.ceph[self.config.get('cluster')].thrashers for t in thrashers: if not isinstance(t, MonitorThrasher) and hasattr(t, 'switch_thrasher') and ( isinstance(t.stopping, Event) and not t.stopping.is_set() ): other_thrasher = t self.log('switch_task: waiting for others thrashers') other_thrasher.switch_thrasher.wait(300) self.log('switch_task: done waiting for the other thrasher') other_thrasher.switch_thrasher.clear() def _do_thrash(self): """ Continuously loop and thrash the monitors. """ #status before mon thrashing if self.mds_failover: oldstatus = self.mds_cluster.status() 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.is_set(): 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: try: s = self._wait_until_quorum(m, len(mons), timeout=30) except Exception as e: self.log('mon.{m} is not in quorum size, exception: {e}'.format(m=m,e=e)) self.log('mon_status: {s}'.format(s=s)) 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 try: s = self._wait_until_quorum(m, len(mons)-len(mons_to_kill), timeout=30) except Exception as e: self.log('mon.{m} is not in quorum size, exception: {e}'.format(m=m,e=e)) self.log('mon_status: {s}'.format(s=s)) 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) self.switch_task() 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: try: s = self._wait_until_quorum(m, len(mons), timeout=30) except Exception as e: self.log('mon.{m} is not in quorum size, exception: {e}'.format(m=m,e=e)) self.log('mon_status: {s}'.format(s=s)) 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('mon', 'scrub') except Exception as e: log.warning("Ignoring exception while triggering scrub: %s", e) 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) self.switch_task() #status after thrashing if self.mds_failover: status = self.mds_cluster.status() assert not oldstatus.hadfailover(status), \ 'MDS Failover' @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' if 'cluster' not in config: config['cluster'] = 'ceph' logger = config.get('logger', 'mon_thrasher') log.info('Beginning mon_thrash...') first_mon = teuthology.get_first_mon(ctx, config) (mon,) = ctx.cluster.only(first_mon).remotes.keys() manager = ceph_manager.CephManager( mon, ctx=ctx, logger=log.getChild('ceph_manager'), ) thrash_proc = MonitorThrasher(ctx, manager, config, "MonitorThrasher", logger=log.getChild(logger)) ctx.ceph[config['cluster']].thrashers.append(thrash_proc) try: log.debug('Yielding') yield finally: log.info('joining mon_thrasher') thrash_proc.stop_and_join() mons = _get_mons(ctx) manager.wait_for_mon_quorum_size(len(mons))