def DisableSlowestSupplementalServers(self, multiplier=TOO_DISTANT_MULTIPLIER, max_servers=None,
prefer_asn=None):
"""Disable servers who's fastest duration is multiplier * average of best 10 servers."""
if not max_servers:
max_servers = self.max_servers_to_check
supplemental_servers = self.enabled_supplemental
fastest = [x for x in self.SortEnabledByFastest()][:10]
best_10 = util.CalculateListAverage([x.fastest_check_duration for x in fastest])
cutoff = best_10 * multiplier
self.msg("Removing secondary nameservers slower than %0.2fms (max=%s)" % (cutoff, max_servers))
for (idx, ns) in enumerate(self.SortEnabledByFastest()):
hide = False
if ns not in supplemental_servers:
continue
if ns.fastest_check_duration > cutoff:
hide = True
if idx > max_servers:
hide = True
if hide:
matches = ns.MatchesTags(nameserver.PROVIDER_TAGS)
if matches:
self.msg("%s seems slow, but has tag: %s" % (ns, matches))
else:
ns.tags.add('hidden')
def ComputeAverages(self):
"""Process all runs for all hosts, yielding an average for each host."""
if len(self.results) in self.cached_averages:
return self.cached_averages[len(self.results)]
records = []
for ns in self.results:
if ns.disabled:
continue
failure_count = 0
nx_count = 0
run_averages = []
for test_run in self.results[ns]:
# x: record, req_type, duration, response
total_count = len(test_run)
failure_count += len([x for x in test_run if not x[3]])
nx_count += len(
[x for x in test_run if x[3] and not x[3].answer])
duration = sum([x[2] for x in test_run])
run_averages.append(duration / len(test_run))
# This appears to be a safe use of averaging averages
overall_average = util.CalculateListAverage(run_averages)
(fastest,
slowest) = self.FastestAndSlowestDurationForNameServer(ns)
records.append((ns, overall_average, run_averages, fastest,
slowest, failure_count, nx_count, total_count))
self.cached_averages[len(self.results)] = records
return self.cached_averages[len(self.results)]
def CheckConnectionQuality(self):
"""Look how healthy our DNS connection quality. Averages check durations."""
is_connection_offline = True
durations = []
self.msg('Checking query interception status...')
(intercepted, i_duration) = self.GetInterceptionStatus()
if i_duration:
is_connection_offline = False
durations.append(i_duration)
try_count = 3
for i in range(try_count):
self.msg('Checking connection quality',
count=i + 1,
total=try_count)
if self.primary:
(broken, unused_warning,
n_duration) = self.GetNegativeResponseDuration()
if not broken:
is_connection_offline = False
durations.append(n_duration)
(unused_response, g_duration,
error_msg) = self.GetGoogleResponseDuration()
durations.append(g_duration)
if not error_msg:
is_connection_offline = False
if is_connection_offline and (i + 1) != try_count:
self.msg(
'The internet connection appears to be offline (%s of %s)'
% (i + 1, try_count))
time.sleep(0.2)
if is_connection_offline:
raise OfflineConnection(
'It would appear that your internet connection is offline. '
'namebench is not gettng a response for DNS queries to '
'%s, %s, or %s.' % (self.primary.ip, GOOGLE_NS, OPENDNS_NS))
duration = util.CalculateListAverage(durations)
congestion = duration / EXPECTED_CONGESTION_DURATION
self.msg('Congestion level is %2.2fX (check duration: %2.2fms)' %
(congestion, duration))
if congestion > 1:
# multiplier is
multiplier = 1 + ((congestion - 1) * CONGESTION_OFFSET_MULTIPLIER)
if multiplier > MAX_CONGESTION_MULTIPLIER:
multiplier = MAX_CONGESTION_MULTIPLIER
else:
multiplier = 1
return (intercepted, congestion, multiplier, duration)
def CheckConnectionQuality(self):
"""Look how healthy our DNS connection quality. Averages check durations."""
is_connection_offline = True
self.msg('Checking query interception status...')
odns = providers.OpenDNS()
(intercepted, i_duration) = odns.InterceptionStateWithDuration()
if i_duration:
is_connection_offline = False
durations = []
try_count = 3
for i in range(try_count):
self.msg('Checking connection quality',
count=i + 1,
total=try_count)
if self.primary:
(broken, unused_warning,
n_duration) = self.GetNegativeResponseDuration()
if not broken:
is_connection_offline = False
durations.append(n_duration)
(unused_response, g_duration,
error_msg) = self.GetGoogleResponseDuration()
if not error_msg:
durations.append(g_duration)
is_connection_offline = False
if is_connection_offline and (i + 1) != try_count:
self.msg(
'The internet connection appears to be offline (%s of %s)'
% (i + 1, try_count))
time.sleep(0.2)
if is_connection_offline:
raise OfflineConnection(
'It would appear that your internet connection is offline.'
'namebench is not gettng a response for DNS queries to '
'%s, %s, or %s.' %
(self.primary.ip, providers.GOOGLE_IP, providers.OPENDNS_IP))
avg_latency_s = util.CalculateListAverage(durations) / 1000.0
max_latency_s = max(durations) / 1000.0
self.msg("Average DNS lookup latency: %.2fs Maximum: %.2fs" %
(avg_latency_s, max_latency_s))
return (intercepted, avg_latency_s, max_latency_s)
def DisableDistantServers(self,
multiplier=TOO_DISTANT_MULTIPLIER,
max_servers=MAX_NEARBY_SERVERS):
"""Disable servers who's fastest duration is multiplier * average of best 10 servers."""
self.RemoveBrokenServers(delete_unwanted=True)
secondaries = self.secondaries
fastest = [x for x in self.SortByFastest() if not x.disabled][:10]
best_10 = util.CalculateListAverage(
[x.fastest_check_duration for x in fastest])
cutoff = best_10 * multiplier
self.msg(
"Removing secondary nameservers slower than %0.2fms (max=%s)" %
(cutoff, max_servers))
for idx, ns in enumerate(secondaries):
if (ns.fastest_check_duration > cutoff) or idx > max_servers:
self.remove(ns)
def _GenerateNameServerSummary(self):
if self.cached_summary:
return self.cached_summary
nsdata = {}
sorted_averages = sorted(self.ComputeAverages(),
key=operator.itemgetter(1))
placed_at = -1
fastest = {}
fastest_nonglobal = {}
reference = {}
# Fill in basic information for all nameservers, even those without scores.
fake_position = 1000
for ns in sorted(self.nameservers,
key=operator.attrgetter('check_average')):
fake_position += 1
nsdata[ns] = {
'ip': ns.ip,
'name': ns.name,
'hostname': ns.hostname,
'version': ns.version,
'node_ids': list(ns.node_ids),
'sys_position': ns.system_position,
'is_failure_prone': ns.is_failure_prone,
'duration_min': float(ns.fastest_check_duration),
'is_global': ns.is_global,
'is_regional': ns.is_regional,
'is_custom': ns.is_custom,
'is_reference': False,
'is_disabled': bool(ns.disabled),
'check_average': ns.check_average,
'error_count': ns.error_count,
'timeout_count': ns.timeout_count,
'notes': url_map.CreateNoteUrlTuples(ns.notes),
'port_behavior': ns.port_behavior,
'position': fake_position
}
# Fill the scores in.
for (ns, unused_avg, run_averages, fastest, slowest, unused_failures,
nx_count, unused_total) in sorted_averages:
placed_at += 1
durations = []
for _ in self.results[ns]:
durations.append([x[2] for x in self.results[ns][0]])
nsdata[ns].update({
'position':
placed_at,
'overall_average':
util.CalculateListAverage(run_averages),
'averages':
run_averages,
'duration_min':
float(fastest),
'duration_max':
slowest,
'nx_count':
nx_count,
'durations':
durations,
'index':
self._GenerateIndexSummary(ns),
})
# Determine which nameserver to refer to for improvement scoring
if not ns.disabled:
if ns.system_position == 0:
reference = ns
elif not fastest_nonglobal and not ns.is_global:
fastest_nonglobal = ns
# If no reference was found, use the fastest non-global nameserver record.
if not reference:
if fastest_nonglobal:
reference = fastest_nonglobal
else:
# The second ns.
reference = sorted_averages[1][0]
# Update the improvement scores for each nameserver.
for ns in nsdata:
if nsdata[ns]['ip'] != nsdata[reference]['ip']:
if 'overall_average' in nsdata[ns]:
nsdata[ns]['diff'] = (
(nsdata[reference]['overall_average'] /
nsdata[ns]['overall_average']) - 1) * 100
else:
nsdata[ns]['is_reference'] = True
# print "--- DEBUG: %s ---" % ns
# print nsdata[ns]
# if 'index' in nsdata[ns]:
# print "index length: %s" % len(nsdata[ns]['index'])
# print ""
self.cached_summary = sorted(nsdata.values(),
key=operator.itemgetter('position'))
return self.cached_summary
def testCalculateListAverage(self):
self.assertEqual(util.CalculateListAverage([3, 2, 2]),
2.3333333333333335)
def check_average(self):
# If we only have a ping result, sort by it. Otherwise, use all non-ping results.
if len(self.checks) == 1:
return self.checks[0][3]
else:
return util.CalculateListAverage([x[3] for x in self.checks[1:]])
def check_average(self):
return util.CalculateListAverage(
[x.check_average for x in self if not x.disabled])
