blob: e62a62a935e71f878438e2b09111966ab7e5f4f3 (
plain)
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
|
# frozen_string_literal: true
require 'logger'
module Gitlab
module Metrics
module Samplers
class BaseSampler < Daemon
attr_reader :interval
# interval - The sampling interval in seconds.
# warmup - When true, takes a single sample eagerly before entering the sampling loop.
# This can be useful to ensure that all metrics files exist after `start` returns,
# since prometheus-client-mmap creates them lazily upon first access.
def initialize(interval: nil, logger: Logger.new($stdout), warmup: false, **options)
interval ||= ENV[interval_env_key]&.to_i
interval ||= self.class::DEFAULT_SAMPLING_INTERVAL_SECONDS
interval_half = interval.to_f / 2
@interval = interval
@interval_steps = (-interval_half..interval_half).step(0.1).to_a
@logger = logger
@warmup = warmup
super(**options)
end
def safe_sample
sample
rescue StandardError => e
@logger.warn("#{self.class}: #{e}, stopping")
stop
end
def sample
raise NotImplementedError
end
# Returns the sleep interval with a random adjustment.
#
# The random adjustment is put in place to ensure we:
#
# 1. Don't generate samples at the exact same interval every time (thus
# potentially missing anything that happens in between samples).
# 2. Don't sample data at the same interval two times in a row.
def sleep_interval
while step = @interval_steps.sample
next if step == @last_step
@last_step = step
return @interval + @last_step
end
end
private
attr_reader :running
def sampler_class
self.class.name.demodulize
end
def interval_env_key
"#{sampler_class.underscore.upcase}_INTERVAL_SECONDS"
end
def start_working
@running = true
safe_sample if @warmup
true
end
def run_thread
sleep(sleep_interval)
while running
safe_sample
sleep(sleep_interval)
end
end
def stop_working
@running = false
end
end
end
end
end
|
