k3s/vendor/k8s.io/kubernetes/pkg/kubectl/cmd/profiling.go

89 lines
2.0 KiB
Go

/*
Copyright 2017 The Kubernetes 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.
*/
package cmd
import (
"fmt"
"os"
"runtime"
"runtime/pprof"
"github.com/spf13/pflag"
)
var (
profileName string
profileOutput string
)
func addProfilingFlags(flags *pflag.FlagSet) {
flags.StringVar(&profileName, "profile", "none", "Name of profile to capture. One of (none|cpu|heap|goroutine|threadcreate|block|mutex)")
flags.StringVar(&profileOutput, "profile-output", "profile.pprof", "Name of the file to write the profile to")
}
func initProfiling() error {
switch profileName {
case "none":
return nil
case "cpu":
f, err := os.Create(profileOutput)
if err != nil {
return err
}
return pprof.StartCPUProfile(f)
// Block and mutex profiles need a call to Set{Block,Mutex}ProfileRate to
// output anything. We choose to sample all events.
case "block":
runtime.SetBlockProfileRate(1)
return nil
case "mutex":
runtime.SetMutexProfileFraction(1)
return nil
default:
// Check the profile name is valid.
if profile := pprof.Lookup(profileName); profile == nil {
return fmt.Errorf("unknown profile '%s'", profileName)
}
}
return nil
}
func flushProfiling() error {
switch profileName {
case "none":
return nil
case "cpu":
pprof.StopCPUProfile()
case "heap":
runtime.GC()
fallthrough
default:
profile := pprof.Lookup(profileName)
if profile == nil {
return nil
}
f, err := os.Create(profileOutput)
if err != nil {
return err
}
profile.WriteTo(f, 0)
}
return nil
}