Node_Exporter/collector/cpu_linux_test.go
Ben Kochie 73c9a10d37
Handle small backwards jumps in CPU idle
The Linux CPU idle stat can also jump backwards slightly in some cases.
Allow the jump back up to 3 seconds before we attempt to reset the CPU
counter cache.

Fixes: https://github.com/prometheus/node_exporter/issues/1903

Signed-off-by: Ben Kochie <superq@gmail.com>
2021-07-07 12:24:46 +02:00

106 lines
2.4 KiB
Go

// Copyright 2021 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build !nocpu
package collector
import (
"reflect"
"testing"
"github.com/go-kit/log"
"github.com/prometheus/procfs"
)
func makeTestCPUCollector(s []procfs.CPUStat) *cpuCollector {
dup := make([]procfs.CPUStat, len(s))
copy(dup, s)
return &cpuCollector{
logger: log.NewNopLogger(),
cpuStats: dup,
}
}
func TestCPU(t *testing.T) {
firstCPUStat := []procfs.CPUStat{{
User: 100.0,
Nice: 100.0,
System: 100.0,
Idle: 100.0,
Iowait: 100.0,
IRQ: 100.0,
SoftIRQ: 100.0,
Steal: 100.0,
Guest: 100.0,
GuestNice: 100.0,
}}
c := makeTestCPUCollector(firstCPUStat)
want := []procfs.CPUStat{{
User: 101.0,
Nice: 101.0,
System: 101.0,
Idle: 101.0,
Iowait: 101.0,
IRQ: 101.0,
SoftIRQ: 101.0,
Steal: 101.0,
Guest: 101.0,
GuestNice: 101.0,
}}
c.updateCPUStats(want)
got := c.cpuStats
if !reflect.DeepEqual(want, got) {
t.Fatalf("should have %v CPU Stat: got %v", want, got)
}
c = makeTestCPUCollector(firstCPUStat)
jumpBack := []procfs.CPUStat{{
User: 99.9,
Nice: 99.9,
System: 99.9,
Idle: 99.9,
Iowait: 99.9,
IRQ: 99.9,
SoftIRQ: 99.9,
Steal: 99.9,
Guest: 99.9,
GuestNice: 99.9,
}}
c.updateCPUStats(jumpBack)
got = c.cpuStats
if reflect.DeepEqual(jumpBack, got) {
t.Fatalf("should have %v CPU Stat: got %v", firstCPUStat, got)
}
c = makeTestCPUCollector(firstCPUStat)
resetIdle := []procfs.CPUStat{{
User: 102.0,
Nice: 102.0,
System: 102.0,
Idle: 1.0,
Iowait: 102.0,
IRQ: 102.0,
SoftIRQ: 102.0,
Steal: 102.0,
Guest: 102.0,
GuestNice: 102.0,
}}
c.updateCPUStats(resetIdle)
got = c.cpuStats
if !reflect.DeepEqual(resetIdle, got) {
t.Fatalf("should have %v CPU Stat: got %v", resetIdle, got)
}
}