gitlab-org--gitlab-foss/spec/lib/gitlab/metrics/samplers/ruby_sampler_spec.rb
Ben Kochie 78a9991543
Cleanup ruby sampler metrics
* Use a simple counter for sampler duration instead of a histogram.
* Use a counter to collect GC time.
* Remove unused objects metric.
* Cleanup metric names to match Prometheus conventions.
* Prefix generic GC stats with `gc_stat`.
* Include worker label on memory and file descriptor metrics.
2018-06-22 14:12:22 +02:00

61 lines
1.7 KiB
Ruby

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 '#sample' do
it 'samples various statistics' do
expect(Gitlab::Metrics::System).to receive(:memory_usage)
expect(Gitlab::Metrics::System).to receive(:file_descriptor_count)
expect(sampler).to receive(:sample_gc)
sampler.sample
end
it 'adds a metric containing the memory usage' do
expect(Gitlab::Metrics::System).to receive(:memory_usage).and_return(9000)
expect(sampler.metrics[:memory_usage]).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 'clears any GC profiles' do
expect(GC::Profiler).to receive(:clear)
sampler.sample
end
end
describe '#sample_gc' do
it 'adds a metric containing garbage collection time statistics' do
expect(GC::Profiler).to receive(:total_time).and_return(0.24)
expect(sampler.metrics[:total_time]).to receive(:increment).with({}, 0.24)
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