bin/start-impala-cluster.py - impala - Git at Google

 #!/usr/bin/env impala-python
 #
 # Licensed to the Apache Software Foundation (ASF) under one
 # or more contributor license agreements.  See the NOTICE file
 # distributed with this work for additional information
 # regarding copyright ownership.  The ASF licenses this file
 # to you under the Apache License, Version 2.0 (the
 # "License"); you may not use this file except in compliance
 # with the License.  You may obtain a copy of the License at
 #
 #   http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing,
 # software distributed under the License is distributed on an
 # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.

 # Starts up an Impala cluster (ImpalaD + State Store) with the specified number of
 # ImpalaD instances. Each ImpalaD runs on a different port allowing this to be run
 # on a single machine.
 import os
 import psutil
 import sys
 from getpass import getuser
 from time import sleep, time
 from optparse import OptionParser
 from testdata.common import cgroups

 KUDU_MASTER_HOSTS = os.getenv('KUDU_MASTER_HOSTS', '127.0.0.1')
 DEFAULT_IMPALA_MAX_LOG_FILES = os.environ.get('IMPALA_MAX_LOG_FILES', 10)


 # Options
 parser = OptionParser()
 parser.add_option("-s", "--cluster_size", type="int", dest="cluster_size", default=3,
                   help="Size of the cluster (number of impalad instances to start).")
 parser.add_option("-c", "--num_coordinators", type="int", dest="num_coordinators",
                   default=3, help="Number of coordinators.")
 parser.add_option("--use_exclusive_coordinators", dest="use_exclusive_coordinators",
                   action="store_true", default=False, help="If true, coordinators only "
                   "coordinate queries and execute coordinator fragments. If false, "
                   "coordinators also act as executors.")
 parser.add_option("--build_type", dest="build_type", default= 'latest',
                   help="Build type to use - debug / release / latest")
 parser.add_option("--impalad_args", dest="impalad_args", action="append", type="string",
                   default=[],
                   help="Additional arguments to pass to each Impalad during startup")
 parser.add_option("--state_store_args", dest="state_store_args", action="append",
                   type="string", default=[],
                   help="Additional arguments to pass to State Store during startup")
 parser.add_option("--catalogd_args", dest="catalogd_args", action="append",
                   type="string", default=[],
                   help="Additional arguments to pass to the Catalog Service at startup")
 parser.add_option("--kill", "--kill_only", dest="kill_only", action="store_true",
                   default=False, help="Instead of starting the cluster, just kill all"
                   " the running impalads and the statestored.")
 parser.add_option("--force_kill", dest="force_kill", action="store_true", default=False,
                   help="Force kill impalad and statestore processes.")
 parser.add_option("-r", "--restart_impalad_only", dest="restart_impalad_only",
                   action="store_true", default=False,
                   help="Restarts only the impalad processes")
 parser.add_option("--in-process", dest="inprocess", action="store_true", default=False,
                   help="Start all Impala backends and state store in a single process.")
 parser.add_option("--log_dir", dest="log_dir",
                   default=os.environ['IMPALA_CLUSTER_LOGS_DIR'],
                   help="Directory to store output logs to.")
 parser.add_option('--max_log_files', default=DEFAULT_IMPALA_MAX_LOG_FILES,
                   help='Max number of log files before rotation occurs.')
 parser.add_option("-v", "--verbose", dest="verbose", action="store_true", default=False,
                   help="Prints all output to stderr/stdout.")
 parser.add_option("--wait_for_cluster", dest="wait_for_cluster", action="store_true",
                   default=False, help="Wait until the cluster is ready to accept "
                   "queries before returning.")
 parser.add_option("--log_level", type="int", dest="log_level", default=1,
                    help="Set the impalad backend logging level")
 parser.add_option("--jvm_args", dest="jvm_args", default="",
                   help="Additional arguments to pass to the JVM(s) during startup.")
 parser.add_option("--kudu_master_hosts", default=KUDU_MASTER_HOSTS,
                   help="The host name or address of the Kudu master. Multiple masters "
                       "can be specified using a comma separated list.")

 options, args = parser.parse_args()

 IMPALA_HOME = os.environ['IMPALA_HOME']
 KNOWN_BUILD_TYPES = ['debug', 'release', 'latest']
 IMPALAD_PATH = os.path.join(IMPALA_HOME,
     'bin/start-impalad.sh -build_type=%s' % options.build_type)
 STATE_STORE_PATH = os.path.join(IMPALA_HOME,
     'bin/start-statestored.sh -build_type=%s' % options.build_type)
 CATALOGD_PATH = os.path.join(IMPALA_HOME,
     'bin/start-catalogd.sh -build_type=%s' % options.build_type)
 MINI_IMPALA_CLUSTER_PATH = IMPALAD_PATH + " -in-process"

 IMPALA_SHELL = os.path.join(IMPALA_HOME, 'bin/impala-shell.sh')
 IMPALAD_PORTS = ("-beeswax_port=%d -hs2_port=%d  -be_port=%d "
                  "-state_store_subscriber_port=%d -webserver_port=%d")
 JVM_ARGS = "-jvm_debug_port=%s -jvm_args=%s"
 BE_LOGGING_ARGS = "-log_filename=%s -log_dir=%s -v=%s -logbufsecs=5 -max_log_files=%s"
 CLUSTER_WAIT_TIMEOUT_IN_SECONDS = 240
 # Kills have a timeout to prevent automated scripts from hanging indefinitely.
 # It is set to a high value to avoid failing if processes are slow to shut down.
 KILL_TIMEOUT_IN_SECONDS = 240

 def find_user_processes(binaries):
   """Returns an iterator over all processes owned by the current user with a matching
   binary name from the provided list."""
   for pid in psutil.get_pid_list():
     try:
       process = psutil.Process(pid)
       if process.username == getuser() and process.name in binaries: yield process
     except KeyError, e:
       if "uid not found" not in str(e):
         raise
     except psutil.NoSuchProcess, e:
       # Ignore the case when a process no longer exists.
       pass

 def check_process_exists(binary, attempts=1):
   """Checks if a process exists given the binary name. The `attempts` count allows us to
   control the time a process needs to settle until it becomes available. After each try
   the script will sleep for one second and retry. Returns True if it exists and False
   otherwise.
   """
   for _ in range(attempts):
     for proc in find_user_processes([binary]):
       return True
     sleep(1)
   return False

 def exec_impala_process(cmd, args, stderr_log_file_path):
   redirect_output = str()
   if options.verbose:
     args += ' -logtostderr=1'
   else:
     redirect_output = "1>%s" % stderr_log_file_path
   cmd = '%s %s %s 2>&1 &' % (cmd, args, redirect_output)
   os.system(cmd)

 def kill_cluster_processes(force=False):
   binaries = ['catalogd', 'impalad', 'statestored', 'mini-impala-cluster']
   kill_matching_processes(binaries, force)

 def kill_matching_processes(binary_names, force=False):
   """Kills all processes with the given binary name, waiting for them to exit"""
   # Send all the signals before waiting so that processes can clean up in parallel.
   processes = list(find_user_processes(binary_names))
   for process in processes:
     try:
       if force:
         process.kill()
       else:
         process.terminate()
     except psutil.NoSuchProcess:
       pass

   for process in processes:
     try:
       process.wait(KILL_TIMEOUT_IN_SECONDS)
     except psutil.TimeoutExpired:
       raise RuntimeError("Unable to kill %s (pid %d) after %d seconds." % (process.name,
           process.pid, KILL_TIMEOUT_IN_SECONDS))

 def start_statestore():
   print "Starting State Store logging to %s/statestored.INFO" % options.log_dir
   stderr_log_file_path = os.path.join(options.log_dir, "statestore-error.log")
   args = "%s %s" % (build_impalad_logging_args(0, "statestored"),
                     " ".join(options.state_store_args))
   exec_impala_process(STATE_STORE_PATH, args, stderr_log_file_path)
   if not check_process_exists("statestored", 10):
     raise RuntimeError("Unable to start statestored. Check log or file permissions"
                        " for more details.")

 def start_catalogd():
   print "Starting Catalog Service logging to %s/catalogd.INFO" % options.log_dir
   stderr_log_file_path = os.path.join(options.log_dir, "catalogd-error.log")
   args = "%s %s %s" % (build_impalad_logging_args(0, "catalogd"),
                        " ".join(options.catalogd_args),
                        build_jvm_args(options.cluster_size))
   exec_impala_process(CATALOGD_PATH, args, stderr_log_file_path)
   if not check_process_exists("catalogd", 10):
     raise RuntimeError("Unable to start catalogd. Check log or file permissions"
                        " for more details.")

 def start_mini_impala_cluster(cluster_size):
   print ("Starting in-process Impala Cluster logging "
          "to %s/mini-impala-cluster.INFO" % options.log_dir)
   args = "-num_backends=%s %s" %\
          (cluster_size, build_impalad_logging_args(0, 'mini-impala-cluster'))
   stderr_log_file_path = os.path.join(options.log_dir, 'mini-impala-cluster-error.log')
   exec_impala_process(MINI_IMPALA_CLUSTER_PATH, args, stderr_log_file_path)

 def build_impalad_port_args(instance_num):
   BASE_BEESWAX_PORT = 21000
   BASE_HS2_PORT = 21050
   BASE_BE_PORT = 22000
   BASE_STATE_STORE_SUBSCRIBER_PORT = 23000
   BASE_WEBSERVER_PORT = 25000
   return IMPALAD_PORTS % (BASE_BEESWAX_PORT + instance_num, BASE_HS2_PORT + instance_num,
                           BASE_BE_PORT + instance_num,
                           BASE_STATE_STORE_SUBSCRIBER_PORT + instance_num,
                           BASE_WEBSERVER_PORT + instance_num)

 def build_impalad_logging_args(instance_num, service_name):
   return BE_LOGGING_ARGS % (service_name, options.log_dir, options.log_level,
                             options.max_log_files)

 def build_jvm_args(instance_num):
   BASE_JVM_DEBUG_PORT = 30000
   return JVM_ARGS % (BASE_JVM_DEBUG_PORT + instance_num, options.jvm_args)

 def start_impalad_instances(cluster_size, num_coordinators, use_exclusive_coordinators):
   """Start 'cluster_size' impalad instances. The first 'num_coordinator' instances will
     act as coordinators. 'use_exclusive_coordinators' specifies whether the coordinators
     will only execute coordinator fragments."""
   if cluster_size == 0:
     # No impalad instances should be started.
     return

   # The default memory limit for an impalad is 80% of the total system memory. On a
   # mini-cluster with 3 impalads that means 240%. Since having an impalad be OOM killed
   # is very annoying, the mem limit will be reduced. This can be overridden using the
   # --impalad_args flag. virtual_memory().total returns the total physical memory.
   mem_limit = int(0.8 * psutil.virtual_memory().total / cluster_size)

   # Start each impalad instance and optionally redirect the output to a log file.
   for i in range(cluster_size):
     if i == 0:
       # The first impalad always logs to impalad.INFO
       service_name = "impalad"
     else:
       service_name = "impalad_node%s" % i
       # Sleep between instance startup: simultaneous starts hurt the minikdc
       # Yes, this is a hack, but it's easier than modifying the minikdc...
       # TODO: is this really necessary?
       sleep(1)

     print "Starting Impala Daemon logging to %s/%s.INFO" % (options.log_dir,
         service_name)

     # impalad args from the --impalad_args flag. Also replacing '#ID' with the instance.
     param_args = (" ".join(options.impalad_args)).replace("#ID", str(i))
     args = "--mem_limit=%s %s %s %s %s" %\
           (mem_limit,  # Goes first so --impalad_args will override it.
            build_impalad_logging_args(i, service_name), build_jvm_args(i),
            build_impalad_port_args(i), param_args)
     if options.kudu_master_hosts:
       # Must be prepended, otherwise the java options interfere.
       args = "-kudu_master_hosts %s %s" % (options.kudu_master_hosts, args)

     if i >= num_coordinators:
       args = "-is_coordinator=false %s" % (args)
     elif use_exclusive_coordinators:
       # Coordinator instance that doesn't execute non-coordinator fragments
       args = "-is_executor=false %s" % (args)

     stderr_log_file_path = os.path.join(options.log_dir, '%s-error.log' % service_name)
     exec_impala_process(IMPALAD_PATH, args, stderr_log_file_path)

 def wait_for_impala_process_count(impala_cluster, retries=10):
   """Checks that the desired number of impalad/statestored processes are running.

   Refresh until the number running impalad/statestored processes reaches the expected
   number based on CLUSTER_SIZE, or the retry limit is hit. Failing this, raise a
   RuntimeError.
   """
   for i in range(retries):
     if len(impala_cluster.impalads) < options.cluster_size or \
         not impala_cluster.statestored or not impala_cluster.catalogd:
           sleep(1)
           impala_cluster.refresh()
   msg = str()
   if len(impala_cluster.impalads) < options.cluster_size:
     impalads_found = len(impala_cluster.impalads)
     msg += "Expected %d impalad(s), only %d found\n" %\
         (options.cluster_size, impalads_found)
   if not impala_cluster.statestored:
     msg += "statestored failed to start.\n"
   if not impala_cluster.catalogd:
     msg += "catalogd failed to start.\n"
   if msg:
     raise RuntimeError(msg)

 def wait_for_cluster_web(timeout_in_seconds=CLUSTER_WAIT_TIMEOUT_IN_SECONDS):
   """Checks if the cluster is "ready"

   A cluster is deemed "ready" if:
     - All backends are registered with the statestore.
     - Each impalad knows about all other impalads.
   This information is retrieved by querying the statestore debug webpage
   and each individual impalad's metrics webpage.
   """
   impala_cluster = ImpalaCluster()
   # impalad processes may take a while to come up.
   wait_for_impala_process_count(impala_cluster)
   for impalad in impala_cluster.impalads:
     impalad.service.wait_for_num_known_live_backends(options.cluster_size,
         timeout=CLUSTER_WAIT_TIMEOUT_IN_SECONDS, interval=2)
     if impalad._get_arg_value('is_coordinator', default='true') == 'true':
       wait_for_catalog(impalad, timeout_in_seconds=CLUSTER_WAIT_TIMEOUT_IN_SECONDS)

 def wait_for_catalog(impalad, timeout_in_seconds):
   """Waits for the impalad catalog to become ready"""
   start_time = time()
   catalog_ready = False
   attempt = 0
   while (time() - start_time < timeout_in_seconds and not catalog_ready):
     try:
       num_dbs = impalad.service.get_metric_value('catalog.num-databases')
       num_tbls = impalad.service.get_metric_value('catalog.num-tables')
       catalog_ready = impalad.service.get_metric_value('catalog.ready')
       if catalog_ready or attempt % 4 == 0:
           print 'Waiting for Catalog... Status: %s DBs / %s tables (ready=%s)' %\
               (num_dbs, num_tbls, catalog_ready)
       attempt += 1
     except Exception, e:
       print e
     sleep(0.5)
   if not catalog_ready:
     raise RuntimeError('Catalog was not initialized in expected time period.')

 def wait_for_cluster_cmdline(timeout_in_seconds=CLUSTER_WAIT_TIMEOUT_IN_SECONDS):
   """Checks if the cluster is "ready" by executing a simple query in a loop"""
   start_time = time()
   while os.system('%s -i localhost:21000 -q "%s"' %  (IMPALA_SHELL, 'select 1')) != 0:
     if time() - timeout_in_seconds > start_time:
       raise RuntimeError('Cluster did not start within %d seconds' % timeout_in_seconds)
     print 'Cluster not yet available. Sleeping...'
     sleep(2)

 if __name__ == "__main__":
   if options.kill_only:
     kill_cluster_processes(force=options.force_kill)
     sys.exit(0)

   if options.build_type not in KNOWN_BUILD_TYPES:
     print 'Invalid build type %s' % options.build_type
     print 'Valid values: %s' % ', '.join(KNOWN_BUILD_TYPES)
     sys.exit(1)

   if options.cluster_size < 0:
     print 'Please specify a cluster size >= 0'
     sys.exit(1)

   if options.num_coordinators <= 0:
     print 'Please specify a valid number of coordinators > 0'
     sys.exit(1)

   if options.use_exclusive_coordinators and options.num_coordinators >= options.cluster_size:
     print 'Cannot start an Impala cluster with no executors'
     sys.exit(1)

   if not os.path.isdir(options.log_dir):
     print 'Log dir does not exist or is not a directory: %s' % options.log_dir
     sys.exit(1)

   # Kill existing cluster processes based on the current configuration.
   if options.restart_impalad_only:
     if options.inprocess:
       print 'Cannot perform individual component restarts using an in-process cluster'
       sys.exit(1)
     kill_matching_processes(['impalad'], force=options.force_kill)
   else:
     kill_cluster_processes(force=options.force_kill)

   try:
     import json
     wait_for_cluster = wait_for_cluster_web
   except ImportError:
     print "json module not found, checking for cluster startup through the command-line"
     wait_for_cluster = wait_for_cluster_cmdline

   # If ImpalaCluster cannot be imported, fall back to the command-line to check
   # whether impalads/statestore are up.
   try:
     from tests.common.impala_cluster import ImpalaCluster
     if options.restart_impalad_only:
       impala_cluster = ImpalaCluster()
       if not impala_cluster.statestored or not impala_cluster.catalogd:
         print 'No running statestored or catalogd detected. Restarting entire cluster.'
         options.restart_impalad_only = False
   except ImportError:
     print 'ImpalaCluster module not found.'
     # TODO: Update this code path to work similar to the ImpalaCluster code path when
     # restarting only impalad processes. Specifically, we should do a full cluster
     # restart if either the statestored or catalogd processes are down, even if
     # restart_only_impalad=True.
     wait_for_cluster = wait_for_cluster_cmdline

   if options.inprocess:
     # The statestore and the impalads start in the same process.
     start_mini_impala_cluster(options.cluster_size)
     wait_for_cluster_cmdline()
   else:
     try:
       if not options.restart_impalad_only:
         start_statestore()
         start_catalogd()
       start_impalad_instances(options.cluster_size, options.num_coordinators,
           options.use_exclusive_coordinators)
       # Sleep briefly to reduce log spam: the cluster takes some time to start up.
       sleep(3)
       wait_for_cluster()
     except Exception, e:
       print 'Error starting cluster: %s' % e
       sys.exit(1)

   print 'Impala Cluster Running with %d nodes and %d coordinators.' % (
       options.cluster_size, options.num_coordinators)
	#!/usr/bin/env impala-python
	#
	# Licensed to the Apache Software Foundation (ASF) under one
	# or more contributor license agreements. See the NOTICE file
	# distributed with this work for additional information
	# regarding copyright ownership. The ASF licenses this file
	# to you under the Apache License, Version 2.0 (the
	# "License"); you may not use this file except in compliance
	# with the License. You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing,
	# software distributed under the License is distributed on an
	# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	# KIND, either express or implied. See the License for the
	# specific language governing permissions and limitations
	# under the License.

	# Starts up an Impala cluster (ImpalaD + State Store) with the specified number of
	# ImpalaD instances. Each ImpalaD runs on a different port allowing this to be run
	# on a single machine.
	import os
	import psutil
	import sys
	from getpass import getuser
	from time import sleep, time
	from optparse import OptionParser
	from testdata.common import cgroups

	KUDU_MASTER_HOSTS = os.getenv('KUDU_MASTER_HOSTS', '127.0.0.1')
	DEFAULT_IMPALA_MAX_LOG_FILES = os.environ.get('IMPALA_MAX_LOG_FILES', 10)


	# Options
	parser = OptionParser()
	parser.add_option("-s", "--cluster_size", type="int", dest="cluster_size", default=3,
	help="Size of the cluster (number of impalad instances to start).")
	parser.add_option("-c", "--num_coordinators", type="int", dest="num_coordinators",
	default=3, help="Number of coordinators.")
	parser.add_option("--use_exclusive_coordinators", dest="use_exclusive_coordinators",
	action="store_true", default=False, help="If true, coordinators only "
	"coordinate queries and execute coordinator fragments. If false, "
	"coordinators also act as executors.")
	parser.add_option("--build_type", dest="build_type", default= 'latest',
	help="Build type to use - debug / release / latest")
	parser.add_option("--impalad_args", dest="impalad_args", action="append", type="string",
	default=[],
	help="Additional arguments to pass to each Impalad during startup")
	parser.add_option("--state_store_args", dest="state_store_args", action="append",
	type="string", default=[],
	help="Additional arguments to pass to State Store during startup")
	parser.add_option("--catalogd_args", dest="catalogd_args", action="append",
	type="string", default=[],
	help="Additional arguments to pass to the Catalog Service at startup")
	parser.add_option("--kill", "--kill_only", dest="kill_only", action="store_true",
	default=False, help="Instead of starting the cluster, just kill all"
	" the running impalads and the statestored.")
	parser.add_option("--force_kill", dest="force_kill", action="store_true", default=False,
	help="Force kill impalad and statestore processes.")
	parser.add_option("-r", "--restart_impalad_only", dest="restart_impalad_only",
	action="store_true", default=False,
	help="Restarts only the impalad processes")
	parser.add_option("--in-process", dest="inprocess", action="store_true", default=False,
	help="Start all Impala backends and state store in a single process.")
	parser.add_option("--log_dir", dest="log_dir",
	default=os.environ['IMPALA_CLUSTER_LOGS_DIR'],
	help="Directory to store output logs to.")
	parser.add_option('--max_log_files', default=DEFAULT_IMPALA_MAX_LOG_FILES,
	help='Max number of log files before rotation occurs.')
	parser.add_option("-v", "--verbose", dest="verbose", action="store_true", default=False,
	help="Prints all output to stderr/stdout.")
	parser.add_option("--wait_for_cluster", dest="wait_for_cluster", action="store_true",
	default=False, help="Wait until the cluster is ready to accept "
	"queries before returning.")
	parser.add_option("--log_level", type="int", dest="log_level", default=1,
	help="Set the impalad backend logging level")
	parser.add_option("--jvm_args", dest="jvm_args", default="",
	help="Additional arguments to pass to the JVM(s) during startup.")
	parser.add_option("--kudu_master_hosts", default=KUDU_MASTER_HOSTS,
	help="The host name or address of the Kudu master. Multiple masters "
	"can be specified using a comma separated list.")

	options, args = parser.parse_args()

	IMPALA_HOME = os.environ['IMPALA_HOME']
	KNOWN_BUILD_TYPES = ['debug', 'release', 'latest']
	IMPALAD_PATH = os.path.join(IMPALA_HOME,
	'bin/start-impalad.sh -build_type=%s' % options.build_type)
	STATE_STORE_PATH = os.path.join(IMPALA_HOME,
	'bin/start-statestored.sh -build_type=%s' % options.build_type)
	CATALOGD_PATH = os.path.join(IMPALA_HOME,
	'bin/start-catalogd.sh -build_type=%s' % options.build_type)
	MINI_IMPALA_CLUSTER_PATH = IMPALAD_PATH + " -in-process"

	IMPALA_SHELL = os.path.join(IMPALA_HOME, 'bin/impala-shell.sh')
	IMPALAD_PORTS = ("-beeswax_port=%d -hs2_port=%d -be_port=%d "
	"-state_store_subscriber_port=%d -webserver_port=%d")
	JVM_ARGS = "-jvm_debug_port=%s -jvm_args=%s"
	BE_LOGGING_ARGS = "-log_filename=%s -log_dir=%s -v=%s -logbufsecs=5 -max_log_files=%s"
	CLUSTER_WAIT_TIMEOUT_IN_SECONDS = 240
	# Kills have a timeout to prevent automated scripts from hanging indefinitely.
	# It is set to a high value to avoid failing if processes are slow to shut down.
	KILL_TIMEOUT_IN_SECONDS = 240

	def find_user_processes(binaries):
	"""Returns an iterator over all processes owned by the current user with a matching
	binary name from the provided list."""
	for pid in psutil.get_pid_list():
	try:
	process = psutil.Process(pid)
	if process.username == getuser() and process.name in binaries: yield process
	except KeyError, e:
	if "uid not found" not in str(e):
	raise
	except psutil.NoSuchProcess, e:
	# Ignore the case when a process no longer exists.
	pass

	def check_process_exists(binary, attempts=1):
	"""Checks if a process exists given the binary name. The `attempts` count allows us to
	control the time a process needs to settle until it becomes available. After each try
	the script will sleep for one second and retry. Returns True if it exists and False
	otherwise.
	"""
	for _ in range(attempts):
	for proc in find_user_processes([binary]):
	return True
	sleep(1)
	return False

	def exec_impala_process(cmd, args, stderr_log_file_path):
	redirect_output = str()
	if options.verbose:
	args += ' -logtostderr=1'
	else:
	redirect_output = "1>%s" % stderr_log_file_path
	cmd = '%s %s %s 2>&1 &' % (cmd, args, redirect_output)
	os.system(cmd)

	def kill_cluster_processes(force=False):
	binaries = ['catalogd', 'impalad', 'statestored', 'mini-impala-cluster']
	kill_matching_processes(binaries, force)

	def kill_matching_processes(binary_names, force=False):
	"""Kills all processes with the given binary name, waiting for them to exit"""
	# Send all the signals before waiting so that processes can clean up in parallel.
	processes = list(find_user_processes(binary_names))
	for process in processes:
	try:
	if force:
	process.kill()
	else:
	process.terminate()
	except psutil.NoSuchProcess:
	pass

	for process in processes:
	try:
	process.wait(KILL_TIMEOUT_IN_SECONDS)
	except psutil.TimeoutExpired:
	raise RuntimeError("Unable to kill %s (pid %d) after %d seconds." % (process.name,
	process.pid, KILL_TIMEOUT_IN_SECONDS))

	def start_statestore():
	print "Starting State Store logging to %s/statestored.INFO" % options.log_dir
	stderr_log_file_path = os.path.join(options.log_dir, "statestore-error.log")
	args = "%s %s" % (build_impalad_logging_args(0, "statestored"),
	" ".join(options.state_store_args))
	exec_impala_process(STATE_STORE_PATH, args, stderr_log_file_path)
	if not check_process_exists("statestored", 10):
	raise RuntimeError("Unable to start statestored. Check log or file permissions"
	" for more details.")

	def start_catalogd():
	print "Starting Catalog Service logging to %s/catalogd.INFO" % options.log_dir
	stderr_log_file_path = os.path.join(options.log_dir, "catalogd-error.log")
	args = "%s %s %s" % (build_impalad_logging_args(0, "catalogd"),
	" ".join(options.catalogd_args),
	build_jvm_args(options.cluster_size))
	exec_impala_process(CATALOGD_PATH, args, stderr_log_file_path)
	if not check_process_exists("catalogd", 10):
	raise RuntimeError("Unable to start catalogd. Check log or file permissions"
	" for more details.")

	def start_mini_impala_cluster(cluster_size):
	print ("Starting in-process Impala Cluster logging "
	"to %s/mini-impala-cluster.INFO" % options.log_dir)
	args = "-num_backends=%s %s" %\
	(cluster_size, build_impalad_logging_args(0, 'mini-impala-cluster'))
	stderr_log_file_path = os.path.join(options.log_dir, 'mini-impala-cluster-error.log')
	exec_impala_process(MINI_IMPALA_CLUSTER_PATH, args, stderr_log_file_path)

	def build_impalad_port_args(instance_num):
	BASE_BEESWAX_PORT = 21000
	BASE_HS2_PORT = 21050
	BASE_BE_PORT = 22000
	BASE_STATE_STORE_SUBSCRIBER_PORT = 23000
	BASE_WEBSERVER_PORT = 25000
	return IMPALAD_PORTS % (BASE_BEESWAX_PORT + instance_num, BASE_HS2_PORT + instance_num,
	BASE_BE_PORT + instance_num,
	BASE_STATE_STORE_SUBSCRIBER_PORT + instance_num,
	BASE_WEBSERVER_PORT + instance_num)

	def build_impalad_logging_args(instance_num, service_name):
	return BE_LOGGING_ARGS % (service_name, options.log_dir, options.log_level,
	options.max_log_files)

	def build_jvm_args(instance_num):
	BASE_JVM_DEBUG_PORT = 30000
	return JVM_ARGS % (BASE_JVM_DEBUG_PORT + instance_num, options.jvm_args)

	def start_impalad_instances(cluster_size, num_coordinators, use_exclusive_coordinators):
	"""Start 'cluster_size' impalad instances. The first 'num_coordinator' instances will
	act as coordinators. 'use_exclusive_coordinators' specifies whether the coordinators
	will only execute coordinator fragments."""
	if cluster_size == 0:
	# No impalad instances should be started.
	return

	# The default memory limit for an impalad is 80% of the total system memory. On a
	# mini-cluster with 3 impalads that means 240%. Since having an impalad be OOM killed
	# is very annoying, the mem limit will be reduced. This can be overridden using the
	# --impalad_args flag. virtual_memory().total returns the total physical memory.
	mem_limit = int(0.8 * psutil.virtual_memory().total / cluster_size)

	# Start each impalad instance and optionally redirect the output to a log file.
	for i in range(cluster_size):
	if i == 0:
	# The first impalad always logs to impalad.INFO
	service_name = "impalad"
	else:
	service_name = "impalad_node%s" % i
	# Sleep between instance startup: simultaneous starts hurt the minikdc
	# Yes, this is a hack, but it's easier than modifying the minikdc...
	# TODO: is this really necessary?
	sleep(1)

	print "Starting Impala Daemon logging to %s/%s.INFO" % (options.log_dir,
	service_name)

	# impalad args from the --impalad_args flag. Also replacing '#ID' with the instance.
	param_args = (" ".join(options.impalad_args)).replace("#ID", str(i))
	args = "--mem_limit=%s %s %s %s %s" %\
	(mem_limit, # Goes first so --impalad_args will override it.
	build_impalad_logging_args(i, service_name), build_jvm_args(i),
	build_impalad_port_args(i), param_args)
	if options.kudu_master_hosts:
	# Must be prepended, otherwise the java options interfere.
	args = "-kudu_master_hosts %s %s" % (options.kudu_master_hosts, args)

	if i >= num_coordinators:
	args = "-is_coordinator=false %s" % (args)
	elif use_exclusive_coordinators:
	# Coordinator instance that doesn't execute non-coordinator fragments
	args = "-is_executor=false %s" % (args)

	stderr_log_file_path = os.path.join(options.log_dir, '%s-error.log' % service_name)
	exec_impala_process(IMPALAD_PATH, args, stderr_log_file_path)

	def wait_for_impala_process_count(impala_cluster, retries=10):
	"""Checks that the desired number of impalad/statestored processes are running.

	Refresh until the number running impalad/statestored processes reaches the expected
	number based on CLUSTER_SIZE, or the retry limit is hit. Failing this, raise a
	RuntimeError.
	"""
	for i in range(retries):
	if len(impala_cluster.impalads) < options.cluster_size or \
	not impala_cluster.statestored or not impala_cluster.catalogd:
	sleep(1)
	impala_cluster.refresh()
	msg = str()
	if len(impala_cluster.impalads) < options.cluster_size:
	impalads_found = len(impala_cluster.impalads)
	msg += "Expected %d impalad(s), only %d found\n" %\
	(options.cluster_size, impalads_found)
	if not impala_cluster.statestored:
	msg += "statestored failed to start.\n"
	if not impala_cluster.catalogd:
	msg += "catalogd failed to start.\n"
	if msg:
	raise RuntimeError(msg)

	def wait_for_cluster_web(timeout_in_seconds=CLUSTER_WAIT_TIMEOUT_IN_SECONDS):
	"""Checks if the cluster is "ready"

	A cluster is deemed "ready" if:
	- All backends are registered with the statestore.
	- Each impalad knows about all other impalads.
	This information is retrieved by querying the statestore debug webpage
	and each individual impalad's metrics webpage.
	"""
	impala_cluster = ImpalaCluster()
	# impalad processes may take a while to come up.
	wait_for_impala_process_count(impala_cluster)
	for impalad in impala_cluster.impalads:
	impalad.service.wait_for_num_known_live_backends(options.cluster_size,
	timeout=CLUSTER_WAIT_TIMEOUT_IN_SECONDS, interval=2)
	if impalad._get_arg_value('is_coordinator', default='true') == 'true':
	wait_for_catalog(impalad, timeout_in_seconds=CLUSTER_WAIT_TIMEOUT_IN_SECONDS)

	def wait_for_catalog(impalad, timeout_in_seconds):
	"""Waits for the impalad catalog to become ready"""
	start_time = time()
	catalog_ready = False
	attempt = 0
	while (time() - start_time < timeout_in_seconds and not catalog_ready):
	try:
	num_dbs = impalad.service.get_metric_value('catalog.num-databases')
	num_tbls = impalad.service.get_metric_value('catalog.num-tables')
	catalog_ready = impalad.service.get_metric_value('catalog.ready')
	if catalog_ready or attempt % 4 == 0:
	print 'Waiting for Catalog... Status: %s DBs / %s tables (ready=%s)' %\
	(num_dbs, num_tbls, catalog_ready)
	attempt += 1
	except Exception, e:
	print e
	sleep(0.5)
	if not catalog_ready:
	raise RuntimeError('Catalog was not initialized in expected time period.')

	def wait_for_cluster_cmdline(timeout_in_seconds=CLUSTER_WAIT_TIMEOUT_IN_SECONDS):
	"""Checks if the cluster is "ready" by executing a simple query in a loop"""
	start_time = time()
	while os.system('%s -i localhost:21000 -q "%s"' % (IMPALA_SHELL, 'select 1')) != 0:
	if time() - timeout_in_seconds > start_time:
	raise RuntimeError('Cluster did not start within %d seconds' % timeout_in_seconds)
	print 'Cluster not yet available. Sleeping...'
	sleep(2)

	if __name__ == "__main__":
	if options.kill_only:
	kill_cluster_processes(force=options.force_kill)
	sys.exit(0)

	if options.build_type not in KNOWN_BUILD_TYPES:
	print 'Invalid build type %s' % options.build_type
	print 'Valid values: %s' % ', '.join(KNOWN_BUILD_TYPES)
	sys.exit(1)

	if options.cluster_size < 0:
	print 'Please specify a cluster size >= 0'
	sys.exit(1)

	if options.num_coordinators <= 0:
	print 'Please specify a valid number of coordinators > 0'
	sys.exit(1)

	if options.use_exclusive_coordinators and options.num_coordinators >= options.cluster_size:
	print 'Cannot start an Impala cluster with no executors'
	sys.exit(1)

	if not os.path.isdir(options.log_dir):
	print 'Log dir does not exist or is not a directory: %s' % options.log_dir
	sys.exit(1)

	# Kill existing cluster processes based on the current configuration.
	if options.restart_impalad_only:
	if options.inprocess:
	print 'Cannot perform individual component restarts using an in-process cluster'
	sys.exit(1)
	kill_matching_processes(['impalad'], force=options.force_kill)
	else:
	kill_cluster_processes(force=options.force_kill)

	try:
	import json
	wait_for_cluster = wait_for_cluster_web
	except ImportError:
	print "json module not found, checking for cluster startup through the command-line"
	wait_for_cluster = wait_for_cluster_cmdline

	# If ImpalaCluster cannot be imported, fall back to the command-line to check
	# whether impalads/statestore are up.
	try:
	from tests.common.impala_cluster import ImpalaCluster
	if options.restart_impalad_only:
	impala_cluster = ImpalaCluster()
	if not impala_cluster.statestored or not impala_cluster.catalogd:
	print 'No running statestored or catalogd detected. Restarting entire cluster.'
	options.restart_impalad_only = False
	except ImportError:
	print 'ImpalaCluster module not found.'
	# TODO: Update this code path to work similar to the ImpalaCluster code path when
	# restarting only impalad processes. Specifically, we should do a full cluster
	# restart if either the statestored or catalogd processes are down, even if
	# restart_only_impalad=True.
	wait_for_cluster = wait_for_cluster_cmdline

	if options.inprocess:
	# The statestore and the impalads start in the same process.
	start_mini_impala_cluster(options.cluster_size)
	wait_for_cluster_cmdline()
	else:
	try:
	if not options.restart_impalad_only:
	start_statestore()
	start_catalogd()
	start_impalad_instances(options.cluster_size, options.num_coordinators,
	options.use_exclusive_coordinators)
	# Sleep briefly to reduce log spam: the cluster takes some time to start up.
	sleep(3)
	wait_for_cluster()
	except Exception, e:
	print 'Error starting cluster: %s' % e
	sys.exit(1)

	print 'Impala Cluster Running with %d nodes and %d coordinators.' % (
	options.cluster_size, options.num_coordinators)