go-ethereum/metrics/prometheus/collector_test.go
turboboost55 7dc100714d
metrics: add cpu counters (#26796)
This PR adds counter metrics for the CPU system and the Geth process.
Currently the only metrics available for these items are gauges. Gauges are
fine when the consumer scrapes metrics data at the same interval as Geth
produces new values (every 3 seconds), but it is likely that most consumers
will not scrape that often. Intervals of 10, 15, or maybe even 30 seconds
are probably more common.

So the problem is, how does the consumer estimate what the CPU was doing in
between scrapes. With a counter, it's easy ... you just subtract two
successive values and divide by the time to get a nice, accurate average.
But with a gauge, you can't do that. A gauge reading is an instantaneous
picture of what was happening at that moment, but it gives you no idea
about what was going on between scrapes. Taking an average of values is
meaningless.
2023-03-23 14:13:50 +01:00

118 lines
3.0 KiB
Go

package prometheus
import (
"os"
"testing"
"time"
"github.com/ethereum/go-ethereum/metrics"
)
func TestMain(m *testing.M) {
metrics.Enabled = true
os.Exit(m.Run())
}
func TestCollector(t *testing.T) {
c := newCollector()
counter := metrics.NewCounter()
counter.Inc(12345)
c.addCounter("test/counter", counter)
counterfloat64 := metrics.NewCounterFloat64()
counterfloat64.Inc(54321.98)
c.addCounterFloat64("test/counter_float64", counterfloat64)
gauge := metrics.NewGauge()
gauge.Update(23456)
c.addGauge("test/gauge", gauge)
gaugeFloat64 := metrics.NewGaugeFloat64()
gaugeFloat64.Update(34567.89)
c.addGaugeFloat64("test/gauge_float64", gaugeFloat64)
histogram := metrics.NewHistogram(&metrics.NilSample{})
c.addHistogram("test/histogram", histogram)
meter := metrics.NewMeter()
defer meter.Stop()
meter.Mark(9999999)
c.addMeter("test/meter", meter)
timer := metrics.NewTimer()
defer timer.Stop()
timer.Update(20 * time.Millisecond)
timer.Update(21 * time.Millisecond)
timer.Update(22 * time.Millisecond)
timer.Update(120 * time.Millisecond)
timer.Update(23 * time.Millisecond)
timer.Update(24 * time.Millisecond)
c.addTimer("test/timer", timer)
resettingTimer := metrics.NewResettingTimer()
resettingTimer.Update(10 * time.Millisecond)
resettingTimer.Update(11 * time.Millisecond)
resettingTimer.Update(12 * time.Millisecond)
resettingTimer.Update(120 * time.Millisecond)
resettingTimer.Update(13 * time.Millisecond)
resettingTimer.Update(14 * time.Millisecond)
c.addResettingTimer("test/resetting_timer", resettingTimer.Snapshot())
emptyResettingTimer := metrics.NewResettingTimer().Snapshot()
c.addResettingTimer("test/empty_resetting_timer", emptyResettingTimer)
const expectedOutput = `# TYPE test_counter gauge
test_counter 12345
# TYPE test_counter_float64 gauge
test_counter_float64 54321.98
# TYPE test_gauge gauge
test_gauge 23456
# TYPE test_gauge_float64 gauge
test_gauge_float64 34567.89
# TYPE test_histogram_count counter
test_histogram_count 0
# TYPE test_histogram summary
test_histogram {quantile="0.5"} 0
test_histogram {quantile="0.75"} 0
test_histogram {quantile="0.95"} 0
test_histogram {quantile="0.99"} 0
test_histogram {quantile="0.999"} 0
test_histogram {quantile="0.9999"} 0
# TYPE test_meter gauge
test_meter 9999999
# TYPE test_timer_count counter
test_timer_count 6
# TYPE test_timer summary
test_timer {quantile="0.5"} 2.25e+07
test_timer {quantile="0.75"} 4.8e+07
test_timer {quantile="0.95"} 1.2e+08
test_timer {quantile="0.99"} 1.2e+08
test_timer {quantile="0.999"} 1.2e+08
test_timer {quantile="0.9999"} 1.2e+08
# TYPE test_resetting_timer_count counter
test_resetting_timer_count 6
# TYPE test_resetting_timer summary
test_resetting_timer {quantile="0.50"} 12000000
test_resetting_timer {quantile="0.95"} 120000000
test_resetting_timer {quantile="0.99"} 120000000
`
exp := c.buff.String()
if exp != expectedOutput {
t.Log("Expected Output:\n", expectedOutput)
t.Log("Actual Output:\n", exp)
t.Fatal("unexpected collector output")
}
}