github.com/timstclair/heapster@v0.20.0-alpha1/Godeps/_workspace/src/k8s.io/kubernetes/pkg/util/sysctl/sysctl.go (about) 1 /* 2 Copyright 2015 The Kubernetes Authors All rights reserved. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 */ 16 17 package sysctl 18 19 import ( 20 "io/ioutil" 21 "path" 22 "strconv" 23 "strings" 24 ) 25 26 const ( 27 sysctlBase = "/proc/sys" 28 VmOvercommitMemory = "vm/overcommit_memory" 29 VmPanicOnOOM = "vm/panic_on_oom" 30 KernelPanic = "kernel/panic" 31 KernelPanicOnOops = "kernel/panic_on_oops" 32 33 VmOvercommitMemoryAlways = 1 // kernel performs no memory over-commit handling 34 VmPanicOnOOMInvokeOOMKiller = 0 // kernel calls the oom_killer function when OOM occurs 35 36 KernelPanicOnOopsAlways = 1 // kernel panics on kernel oops 37 KernelPanicRebootTimeout = 10 // seconds after a panic for the kernel to reboot 38 ) 39 40 // GetSysctl returns the value for the specified sysctl setting 41 func GetSysctl(sysctl string) (int, error) { 42 data, err := ioutil.ReadFile(path.Join(sysctlBase, sysctl)) 43 if err != nil { 44 return -1, err 45 } 46 val, err := strconv.Atoi(strings.Trim(string(data), " \n")) 47 if err != nil { 48 return -1, err 49 } 50 return val, nil 51 } 52 53 // SetSysctl modifies the specified sysctl flag to the new value 54 func SetSysctl(sysctl string, newVal int) error { 55 return ioutil.WriteFile(path.Join(sysctlBase, sysctl), []byte(strconv.Itoa(newVal)), 0640) 56 }