diff --git a/README.rst b/README.rst
index 5343de67b..16b0c2575 100644
--- a/README.rst
+++ b/README.rst
@@ -112,40 +112,45 @@ is used for all requests.
 
 Run the benchmarking tool using the following command::
 
-    $ zaqar-bench-pc
+    $ zaqar-bench
 
-By default, the command will run a performance test for 3 seconds, using one
-consumer and one producer for each CPU on the system, with 2 greenlet workers
-per CPU per process. You can override these defaults in the config file or on
-the command line using a variety of options. For example, the following
-command runs a performance test for 10 seconds using 4 producer processes with
-20 workers each, plus 1 consumer process with 4 workers::
+By default, the command will run a performance test for 5 seconds, using one
+producer process with 10 greenlet workers, and one observer process with
+5 workers. The consumer role is disabled by default.
 
-    $ zaqar-bench-pc -pp 4 -pw 20 -cp 1 -cw 4 -t 10
+You can override these defaults in the config file or on the command line
+using a variety of options. For example, the following command runs a
+performance test for 30 seconds using 4 producer processes with
+20 workers each, plus 4 consumer processes with 20 workers each. Note that
+the observer role is also disabled in this example by setting its number of
+workers to zero::
 
-By default, the results are in JSON. For more human-readable output add the ``--verbose`` flag.
-Verbose output looks similar to the following::
+    $ zaqar-bench -pp 4 -pw 10 -cw 4 -cw 20 -ow 0 -t 30
 
-    Starting Producer...
+By default, the results are in JSON. For more human-readable output add
+the ``--verbose`` flag. Verbose output looks similar to the following::
 
-    Starting Consumer...
+    $ zaqar-bench --verbose
 
-    Consumer
-    ========
-    duration_sec: 10.2
-    ms_per_claim: 37.6
-    ms_per_delete: 11.8
-    reqs_per_sec: 82.0
-    successful_reqs: 833.0
-    total_reqs: 833.0
+    Starting producer (pp=1 , pw=10)...
+
+    Starting observer (op=1 , ow=5)...
 
     Producer
     ========
-    duration_sec: 10.2
-    ms_per_req: 3.8
-    reqs_per_sec: 1033.6
-    successful_reqs: 10523.0
-    total_reqs: 10523.0
+    duration_sec: 5.1
+    ms_per_req: 2.9
+    reqs_per_sec: 344.5
+    successful_reqs: 1742.0
+    total_reqs: 1742.0
+
+    Observer
+    ========
+    duration_sec: 5.0
+    ms_per_req: 2.9
+    reqs_per_sec: 339.3
+    successful_reqs: 1706.0
+    total_reqs: 1706.0
 
 
 .. _`OpenStack` : http://openstack.org/
diff --git a/bench-requirements.txt b/bench-requirements.txt
index 939afe982..7b0d1dd25 100644
--- a/bench-requirements.txt
+++ b/bench-requirements.txt
@@ -1,5 +1,4 @@
 argparse>=1.2.1
 gevent>=1.0.1
 marktime>=0.2.0
-psutil>=2.1.1
 python-zaqarclient>=0.0.2
diff --git a/setup.cfg b/setup.cfg
index ac53d0c05..7e507b675 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -32,7 +32,7 @@ source-dir = doc/source
 
 [entry_points]
 console_scripts =
-    zaqar-bench-pc = zaqar.bench.conductor:main
+    zaqar-bench = zaqar.bench.conductor:main
     zaqar-server = zaqar.cmd.server:run
     marconi-server = zaqar.cmd.server:run
 
diff --git a/zaqar/bench/conductor.py b/zaqar/bench/conductor.py
index 24ac8fea5..ba92fcd6a 100644
--- a/zaqar/bench/conductor.py
+++ b/zaqar/bench/conductor.py
@@ -17,17 +17,52 @@ from __future__ import print_function
 import json
 import multiprocessing as mp
 
-from zaqar.bench.config import conf
+from zaqarclient.queues.v1 import client
+
+from zaqar.bench import config
 from zaqar.bench import consumer
+from zaqar.bench import observer
 from zaqar.bench import producer
 
+CONF = config.conf
+
+
+def _print_verbose_stats(name, stats):
+    print(name.capitalize())
+    print('=' * len(name))
+
+    values = sorted(stats.items(), key=lambda v: v[0])
+    formatted_vals = ['{}: {:.1f}'.format(*v) for v in values]
+
+    print('\n'.join(formatted_vals))
+    print()  # Blank line
+
+
+def _reset_queues():
+    cli = client.Client(CONF.server_url)
+
+    for i in range(CONF.num_queues):
+        # TODO(kgriffs): DRY up name generation so it is done
+        # in a helper, vs. being copy-pasted everywhere.
+        queue = cli.queue(CONF.queue_prefix + '-' + str(i))
+        queue.delete()
+
 
 def main():
-    conf(project='zaqar', prog='zaqar-benchmark')
+    CONF(project='zaqar', prog='zaqar-benchmark')
+
+    # NOTE(kgriffs): Reset queues since last time. We don't
+    # clean them up after the performance test, in case
+    # the user wants to examine the state of the system.
+    if not CONF.skip_queue_reset:
+        if CONF.verbose:
+            print('Resetting queues...')
+
+        _reset_queues()
 
     downstream_queue = mp.Queue()
     procs = [mp.Process(target=worker.run, args=(downstream_queue,))
-             for worker in [producer, consumer]]
+             for worker in [producer, consumer, observer]]
 
     for each_proc in procs:
         each_proc.start()
@@ -39,29 +74,32 @@ def main():
     for each_proc in procs:
         stats.update(downstream_queue.get_nowait())
 
-    if conf.verbose:
+    if CONF.verbose:
         print()
 
-        for name, stats_group in stats.items():
-            print(name.capitalize())
-            print('=' * len(name))
+        for name in ('producer', 'observer', 'consumer'):
+            stats_group = stats[name]
 
-            values = sorted(stats_group.items(), key=lambda v: v[0])
-            formatted_vals = ["{}: {:.1f}".format(*v) for v in values]
+            # Skip disabled workers
+            if not stats_group['duration_sec']:
+                continue
 
-            print("\n".join(formatted_vals))
-            print('')  # Blank line
+            _print_verbose_stats(name, stats_group)
 
     else:
         stats['params'] = {
             'producer': {
-                'processes': conf.producer_processes,
-                'workers': conf.producer_workers
+                'processes': CONF.producer_processes,
+                'workers': CONF.producer_workers
             },
             'consumer': {
-                'processes': conf.consumer_processes,
-                'workers': conf.consumer_workers
-            }
+                'processes': CONF.consumer_processes,
+                'workers': CONF.consumer_workers
+            },
+            'observer': {
+                'processes': CONF.observer_processes,
+                'workers': CONF.observer_workers
+            },
         }
 
         print(json.dumps(stats))
diff --git a/zaqar/bench/config.py b/zaqar/bench/config.py
index 03dcc108b..e2f7fc76a 100644
--- a/zaqar/bench/config.py
+++ b/zaqar/bench/config.py
@@ -13,38 +13,61 @@
 # limitations under the License.
 
 from oslo.config import cfg
-import psutil
 
 conf = cfg.CONF
 _CLI_OPTIONS = (
     cfg.IntOpt(
         'producer_processes',
         short='pp',
-        default=psutil.NUM_CPUS,
+        default=1,
         help='Number of Producer Processes'),
     cfg.IntOpt(
         'producer_workers',
         short='pw',
-        default=psutil.NUM_CPUS * 2,
+        default=10,
         help='Number of Producer Workers'),
+
     cfg.IntOpt(
         'consumer_processes',
         short='cp',
-        default=psutil.NUM_CPUS,
+        default=1,
         help='Number of Consumer Processes'),
     cfg.IntOpt(
         'consumer_workers',
         short='cw',
-        default=psutil.NUM_CPUS * 2,
+        default=0,
         help='Number of Consumer Workers'),
+
+    cfg.IntOpt(
+        'observer_processes',
+        short='op',
+        default=1,
+        help='Number of Observer Processes'),
+    cfg.IntOpt(
+        'observer_workers',
+        short='ow',
+        default=5,
+        help='Number of Observer Workers'),
+
     cfg.IntOpt('messages_per_claim', short='cno', default=5,
                help=('Number of messages the consumer will attempt to '
                      'claim at a time')),
-    cfg.IntOpt('time', short='t', default=3,
+    cfg.IntOpt('messages_per_list', short='lno', default=5,
+               help=('Number of messages the obserer will attempt to '
+                     'list at a time')),
+
+    cfg.IntOpt('time', short='t', default=5,
                help="Duration of the performance test, in seconds"),
+
     cfg.StrOpt('server_url', short='s', default='http://localhost:8888'),
+
     cfg.StrOpt('queue_prefix', short='q', default='ogre-test-queue'),
     cfg.IntOpt('num_queues', short='qno', default=4),
-    cfg.StrOpt('messages_path', short='m')
+
+    cfg.StrOpt('messages_path', short='m'),
+
+    cfg.BoolOpt('skip_queue_reset', default=False,
+                help=('Do not reset queues before running'
+                      'the performance test')),
 )
 conf.register_cli_opts(_CLI_OPTIONS)
diff --git a/zaqar/bench/consumer.py b/zaqar/bench/consumer.py
index 44da977a2..68d3e2658 100644
--- a/zaqar/bench/consumer.py
+++ b/zaqar/bench/consumer.py
@@ -27,7 +27,9 @@ import marktime
 from zaqarclient.queues.v1 import client
 from zaqarclient.transport.errors import TransportError
 
-from zaqar.bench.config import conf
+from zaqar.bench import config
+
+CONF = config.conf
 
 
 def claim_delete(queues, stats, test_duration, ttl, grace, limit):
@@ -93,8 +95,8 @@ def claim_delete(queues, stats, test_duration, ttl, grace, limit):
 def load_generator(stats, num_workers, num_queues,
                    test_duration, url, ttl, grace, limit):
 
-    cli = client.Client(conf.server_url)
-    queues = [cli.queue(conf.queue_prefix + '-' + str(i))
+    cli = client.Client(CONF.server_url)
+    queues = [cli.queue(CONF.queue_prefix + '-' + str(i))
               for i in range(num_queues)]
 
     gevent.joinall([
@@ -125,9 +127,9 @@ def crunch(stats):
 
 
 def run(upstream_queue):
-    num_procs = conf.consumer_processes
-    num_workers = conf.consumer_workers
-    num_queues = conf.num_queues
+    num_procs = CONF.consumer_processes
+    num_workers = CONF.consumer_workers
+    num_queues = CONF.num_queues
 
     # Stats that will be reported
     duration = 0
@@ -141,17 +143,18 @@ def run(upstream_queue):
 
     # Performance test
     if num_procs and num_workers:
-        test_duration = conf.time
+        test_duration = CONF.time
         stats = mp.Queue()
         # TODO(TheSriram) : Make ttl and grace configurable
         args = (stats, num_workers, num_queues, test_duration,
-                conf.server_url, 300, 200, conf.messages_per_claim)
+                CONF.server_url, 300, 200, CONF.messages_per_claim)
 
         procs = [mp.Process(target=load_generator, args=args)
                  for _ in range(num_procs)]
 
-        if conf.verbose:
-            print("\nStarting Consumer...")
+        if CONF.verbose:
+            print('\nStarting consumers (cp={0}, cw={1})...'.format(
+                  num_procs, num_workers))
 
         start = time.time()
 
diff --git a/zaqar/bench/observer.py b/zaqar/bench/observer.py
new file mode 100644
index 000000000..d49a12a41
--- /dev/null
+++ b/zaqar/bench/observer.py
@@ -0,0 +1,178 @@
+# Copyright (c) 2014 Rackspace, Inc.
+# Licensed 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.
+
+from __future__ import division
+from __future__ import print_function
+
+import multiprocessing as mp
+import random
+import sys
+import time
+
+from gevent import monkey as curious_george
+curious_george.patch_all(thread=False, select=False)
+import gevent
+import marktime
+from six.moves import urllib
+from zaqarclient.queues.v1 import client
+from zaqarclient.transport.errors import TransportError
+
+from zaqar.bench import config
+
+CONF = config.conf
+
+
+#
+# TODO(kgriffs): Factor out the common code from producer, consumer
+# and worker (DRY all the things!)
+#
+
+
+def _extract_marker(links):
+    for link in links:
+        if link['rel'] == 'next':
+            href = link['href']
+            break
+
+    query = urllib.parse.urlparse(href).query
+    params = urllib.parse.parse_qs(query)
+    return params['marker'][0]
+
+
+def observer(queues, stats, test_duration, limit):
+    """Observer Worker
+
+    The observer lists messages without claiming them.
+    """
+
+    end = time.time() + test_duration
+
+    total_elapsed = 0
+    total_succeeded = 0
+    total_failed = 0
+
+    queues = [{'q': q, 'm': None} for q in queues]
+
+    while time.time() < end:
+        # NOTE(kgriffs): Distribute requests across all queues evenly.
+        queue = random.choice(queues)
+
+        try:
+            marktime.start('list_messages')
+            cursor = queue['q'].messages(limit=limit, marker=queue['m'])
+            total_elapsed += marktime.stop('list_messages').seconds
+            total_succeeded += 1
+
+            messages = list(cursor)
+
+            if messages:
+                # TODO(kgriffs): Figure out a less hacky way to do this
+                # while preserving the ability to measure elapsed time
+                # per request.
+                queue['m'] = _extract_marker(cursor._links)
+
+        except TransportError as ex:
+            sys.stderr.write("Could not list messages : {0}\n".format(ex))
+            total_failed += 1
+
+    total_requests = total_succeeded + total_failed
+
+    stats.put({
+        'total_requests': total_requests,
+        'total_succeeded': total_succeeded,
+        'total_elapsed': total_elapsed,
+    })
+
+
+def load_generator(stats, num_workers, num_queues,
+                   test_duration, limit):
+
+    cli = client.Client(CONF.server_url)
+    queues = [cli.queue(CONF.queue_prefix + '-' + str(i))
+              for i in range(num_queues)]
+
+    gevent.joinall([
+        gevent.spawn(observer,
+                     queues, stats, test_duration, limit)
+
+        for _ in range(num_workers)
+    ])
+
+
+def crunch(stats):
+    total_requests = 0
+    total_succeeded = 0
+    total_elapsed = 0.0
+
+    while not stats.empty():
+        entry = stats.get_nowait()
+        total_requests += entry['total_requests']
+        total_succeeded += entry['total_succeeded']
+        total_elapsed += entry['total_elapsed']
+
+    return (total_requests, total_succeeded, total_elapsed)
+
+
+def run(upstream_queue):
+    num_procs = CONF.observer_processes
+    num_workers = CONF.observer_workers
+    num_queues = CONF.num_queues
+
+    # Stats that will be reported
+    duration = 0
+    total_requests = 0
+    total_succeeded = 0
+    throughput = 0
+    latency = 0
+
+    # Performance test
+    if num_procs and num_workers:
+        test_duration = CONF.time
+        stats = mp.Queue()
+        args = (stats, num_workers, num_queues, test_duration,
+                CONF.messages_per_list)
+
+        procs = [mp.Process(target=load_generator, args=args)
+                 for _ in range(num_procs)]
+
+        if CONF.verbose:
+            print('\nStarting observer (op={0}, ow={1})...'.format(
+                  num_procs, num_workers))
+
+        start = time.time()
+
+        for each_proc in procs:
+            each_proc.start()
+
+        for each_proc in procs:
+            each_proc.join()
+
+        (total_requests, total_succeeded, total_elapsed) = crunch(stats)
+
+        duration = time.time() - start
+
+        throughput = total_succeeded / duration
+
+        if total_succeeded:
+            latency = (1000 * total_elapsed / total_succeeded)
+
+    upstream_queue.put({
+        'observer': {
+            'duration_sec': duration,
+            'total_reqs': total_requests,
+            'successful_reqs': total_succeeded,
+            'reqs_per_sec': throughput,
+            'ms_per_req': latency,
+        }
+    })
diff --git a/zaqar/bench/producer.py b/zaqar/bench/producer.py
index 38ec7e015..961a1ca8b 100644
--- a/zaqar/bench/producer.py
+++ b/zaqar/bench/producer.py
@@ -28,7 +28,9 @@ import marktime
 from zaqarclient.queues.v1 import client
 from zaqarclient.transport.errors import TransportError
 
-from zaqar.bench.config import conf
+from zaqar.bench import config
+
+CONF = config.conf
 
 
 def choose_message(message_pool):
@@ -48,7 +50,7 @@ def choose_message(message_pool):
 
 def load_messages():
     default_file_name = 'zaqar-benchmark-messages.json'
-    messages_path = conf.messages_path or conf.find_file(default_file_name)
+    messages_path = CONF.messages_path or CONF.find_file(default_file_name)
     if messages_path:
         with open(messages_path) as f:
             message_pool = json.load(f)
@@ -102,8 +104,8 @@ def producer(queues, message_pool, stats, test_duration):
 # weight them, so can have some busy queues, some not.)
 def load_generator(stats, num_workers, num_queues, test_duration):
 
-    cli = client.Client(conf.server_url)
-    queues = [cli.queue(conf.queue_prefix + '-' + str(i))
+    cli = client.Client(CONF.server_url)
+    queues = [cli.queue(CONF.queue_prefix + '-' + str(i))
               for i in range(num_queues)]
 
     message_pool = load_messages()
@@ -131,9 +133,9 @@ def crunch(stats):
 
 
 def run(upstream_queue):
-    num_procs = conf.producer_processes
-    num_workers = conf.producer_workers
-    num_queues = conf.num_queues
+    num_procs = CONF.producer_processes
+    num_workers = CONF.producer_workers
+    num_queues = CONF.num_queues
 
     duration = 0
     total_requests = 0
@@ -142,7 +144,7 @@ def run(upstream_queue):
     latency = 0
 
     if num_procs and num_workers:
-        test_duration = conf.time
+        test_duration = CONF.time
         stats = mp.Queue()
         args = (stats, num_workers, num_queues, test_duration)
 
@@ -155,8 +157,9 @@ def run(upstream_queue):
             for _ in range(num_procs)
         ]
 
-        if conf.verbose:
-            print('\nStarting Producer...')
+        if CONF.verbose:
+            print('\nStarting producer (pp={0}, pw={1})...'.format(
+                  num_procs, num_workers))
 
         start = time.time()