1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
# frozen_string_literal: true
require_relative '../config/boot'
class MetricsServer # rubocop:disable Gitlab/NamespacedClass
# The singleton instance used to supervise the Puma metrics server.
PumaProcessSupervisor = Class.new(Gitlab::ProcessSupervisor)
class << self
def version
Rails.root.join('GITLAB_METRICS_EXPORTER_VERSION').read.chomp
end
def start_for_puma
metrics_dir = ::Prometheus::Client.configuration.multiprocess_files_dir
start_server = proc do
MetricsServer.spawn('puma', metrics_dir: metrics_dir).tap do |pid|
Gitlab::AppLogger.info("Starting Puma metrics server with pid #{pid}")
end
end
supervisor = PumaProcessSupervisor.instance
supervisor.supervise(start_server.call) do
Gitlab::AppLogger.info('Puma metrics server terminated, restarting...')
start_server.call
end
end
def start_for_sidekiq(**options)
if new_metrics_server?
self.spawn('sidekiq', **options)
else
self.fork('sidekiq', **options)
end
end
def spawn(target, metrics_dir:, **options)
return spawn_ruby_server(target, metrics_dir: metrics_dir, **options) unless new_metrics_server?
name = settings_key(target)
settings = ::Settings.monitoring[name]
path = options[:path]&.then { |p| Pathname.new(p) } || Pathname.new('')
cmd = path.join('gitlab-metrics-exporter').to_path
env = {
'GOGC' => '10', # Set Go GC heap goal to 10% to curb memory growth.
'GME_MMAP_METRICS_DIR' => metrics_dir.to_s,
'GME_PROBES' => 'self,mmap',
'GME_SERVER_HOST' => settings['address'],
'GME_SERVER_PORT' => settings['port'].to_s
}
if settings['log_enabled']
env['GME_LOG_FILE'] = File.join(Rails.root, 'log', "#{name}.log")
env['GME_LOG_LEVEL'] = 'info'
else
env['GME_LOG_LEVEL'] = 'quiet'
end
if settings['tls_enabled']
env['GME_CERT_FILE'] = settings['tls_cert_path']
env['GME_CERT_KEY'] = settings['tls_key_path']
end
Process.spawn(env, cmd, err: $stderr, out: $stdout, pgroup: true).tap do |pid|
Process.detach(pid)
end
end
def spawn_ruby_server(target, metrics_dir:, wipe_metrics_dir: false, **options)
ensure_valid_target!(target)
cmd = "#{Rails.root}/bin/metrics-server"
env = {
'METRICS_SERVER_TARGET' => target,
'WIPE_METRICS_DIR' => wipe_metrics_dir ? '1' : '0',
'GITLAB_CONFIG' => ENV['GITLAB_CONFIG']
}
Process.spawn(env, cmd, err: $stderr, out: $stdout, pgroup: true).tap do |pid|
Process.detach(pid)
end
end
def fork(target, metrics_dir:, wipe_metrics_dir: false, reset_signals: [])
ensure_valid_target!(target)
pid = Process.fork
if pid.nil? # nil means we're inside the fork
# Remove any custom signal handlers the parent process had registered, since we do
# not want to inherit them, and Ruby forks with a `clone` that has the `CLONE_SIGHAND`
# flag set.
Gitlab::ProcessManagement.modify_signals(reset_signals, 'DEFAULT')
server = MetricsServer.new(target, metrics_dir, wipe_metrics_dir)
# This rewrites /proc/cmdline, since otherwise tools like `top` will show the
# parent process `cmdline` which is really confusing.
$0 = server.name
server.start
else
Process.detach(pid)
end
pid
end
private
def new_metrics_server?
Gitlab::Utils.to_boolean(ENV['GITLAB_GOLANG_METRICS_SERVER'])
end
def ensure_valid_target!(target)
raise "Target must be one of [puma,sidekiq]" unless %w(puma sidekiq).include?(target)
end
def settings_key(target)
case target
when 'puma' then 'web_exporter'
when 'sidekiq' then 'sidekiq_exporter'
else ensure_valid_target!(target)
end
end
end
def initialize(target, metrics_dir, wipe_metrics_dir)
@target = target
@metrics_dir = metrics_dir
@wipe_metrics_dir = wipe_metrics_dir
end
def start
::Prometheus::Client.configure do |config|
config.multiprocess_files_dir = @metrics_dir
config.pid_provider = proc { name }
end
FileUtils.mkdir_p(@metrics_dir, mode: 0700)
::Prometheus::CleanupMultiprocDirService.new(@metrics_dir).execute if @wipe_metrics_dir
# We need to `warmup: true` since otherwise the sampler and exporter threads enter
# a race where not all Prometheus db files will be visible to the exporter, resulting
# in missing metrics.
# Warming up ensures that these files exist prior to the exporter starting up.
Gitlab::Metrics::Samplers::RubySampler.initialize_instance(prefix: name, warmup: true).start
default_opts = { gc_requests: true, synchronous: true }
exporter =
case @target
when 'puma'
Gitlab::Metrics::Exporter::WebExporter.instance(**default_opts)
when 'sidekiq'
settings = Settings.new(Settings.monitoring[name])
Gitlab::Metrics::Exporter::SidekiqExporter.instance(settings, **default_opts)
end
exporter.start
end
def name
case @target
when 'puma' then 'web_exporter'
when 'sidekiq' then 'sidekiq_exporter'
end
end
end
|
