gitlab-org--gitlab-foss/spec/lib/gitlab/metrics/samplers/ruby_sampler_spec.rb
2019-08-23 00:15:24 +12:00

99 lines
3.1 KiB
Ruby

# frozen_string_literal: true
require 'spec_helper'
describe Gitlab::Metrics::Samplers::RubySampler do
let(:sampler) { described_class.new(5) }
let(:null_metric) { double('null_metric', set: nil, observe: nil) }
before do
allow(Gitlab::Metrics::NullMetric).to receive(:instance).and_return(null_metric)
end
describe '#initialize' do
it 'sets process_start_time_seconds' do
Timecop.freeze do
expect(sampler.metrics[:process_start_time_seconds].get).to eq(Time.now.to_i)
end
end
end
describe '#sample' do
it 'samples various statistics' do
expect(Gitlab::Metrics::System).to receive(:cpu_time)
expect(Gitlab::Metrics::System).to receive(:file_descriptor_count)
expect(Gitlab::Metrics::System).to receive(:memory_usage)
expect(Gitlab::Metrics::System).to receive(:max_open_file_descriptors)
expect(sampler).to receive(:sample_gc)
sampler.sample
end
it 'adds a metric containing the process resident memory bytes' do
expect(Gitlab::Metrics::System).to receive(:memory_usage).and_return(9000)
expect(sampler.metrics[:process_resident_memory_bytes]).to receive(:set).with({}, 9000)
sampler.sample
end
it 'adds a metric containing the amount of open file descriptors' do
expect(Gitlab::Metrics::System).to receive(:file_descriptor_count)
.and_return(4)
expect(sampler.metrics[:file_descriptors]).to receive(:set).with({}, 4)
sampler.sample
end
it 'adds a metric containing the process total cpu time' do
expect(Gitlab::Metrics::System).to receive(:cpu_time).and_return(0.51)
expect(sampler.metrics[:process_cpu_seconds_total]).to receive(:set).with({}, 0.51)
sampler.sample
end
it 'adds a metric containing the process max file descriptors' do
expect(Gitlab::Metrics::System).to receive(:max_open_file_descriptors).and_return(1024)
expect(sampler.metrics[:process_max_fds]).to receive(:set).with({}, 1024)
sampler.sample
end
it 'clears any GC profiles' do
expect(GC::Profiler).to receive(:clear).at_least(:once)
sampler.sample
end
end
describe '#sample_gc' do
let!(:sampler) { described_class.new(5) }
let(:gc_reports) { [{ GC_TIME: 0.1 }, { GC_TIME: 0.2 }, { GC_TIME: 0.3 }] }
it 're-enables GC::Profiler if needed' do
expect(GC::Profiler).to receive(:enable)
sampler.sample
end
it 'observes GC cycles time' do
expect(sampler).to receive(:sample_gc_reports).and_return(gc_reports)
expect(sampler.metrics[:gc_duration_seconds]).to receive(:observe).with({}, 0.1).ordered
expect(sampler.metrics[:gc_duration_seconds]).to receive(:observe).with({}, 0.2).ordered
expect(sampler.metrics[:gc_duration_seconds]).to receive(:observe).with({}, 0.3).ordered
sampler.sample
end
it 'adds a metric containing garbage collection statistics' do
GC.stat.keys.each do |key|
expect(sampler.metrics[key]).to receive(:set).with({}, anything)
end
sampler.sample
end
end
end