go-osstat

README

OS system statistics library for Go

This is a library to get system metrics like cpu load and memory usage. The library is created for mackerel-agent.

Example

package main

import (
	"fmt"
	"os"

	"github.com/mackerelio/go-osstat/memory"
)

func main() {
	memory, err := memory.Get()
	if err != nil {
		fmt.Fprintf(os.Stderr, "%s\n", err)
		return
	}
	fmt.Printf("memory total: %d bytes\n", memory.Total)
	fmt.Printf("memory used: %d bytes\n", memory.Used)
	fmt.Printf("memory cached: %d bytes\n", memory.Cached)
	fmt.Printf("memory free: %d bytes\n", memory.Free)
}

Supported OS

	loadavg	uptime	cpu	memory	network	disk i/o
Linux	yes	yes	yes	yes	yes	yes
Darwin	yes	yes	*1	yes	yes	no
FreeBSD	yes	yes	no	yes	yes	no
NetBSD	yes	yes	no	no	yes	no
OpenBSD	yes	yes	no	no	no	no
Windows	no	yes	no	yes	no	no

*1: unavailable without cgo

Note for counter values

This library returns the counter value for cpu, network and disk I/O statistics by design. To get the cpu usage in percent, network traffic in kB/s or disk IOPS, sleep for a while and calculate the difference.

package main

import (
	"fmt"
	"os"
	"time"

	"github.com/mackerelio/go-osstat/cpu"
)

func main() {
	before, err := cpu.Get()
	if err != nil {
		fmt.Fprintf(os.Stderr, "%s\n", err)
		return
	}
	time.Sleep(time.Duration(1) * time.Second)
	after, err := cpu.Get()
	if err != nil {
		fmt.Fprintf(os.Stderr, "%s\n", err)
		return
	}
	total := float64(after.Total - before.Total)
	fmt.Printf("cpu user: %f %%\n", float64(after.User-before.User)/total*100)
	fmt.Printf("cpu system: %f %%\n", float64(after.System-before.System)/total*100)
	fmt.Printf("cpu idle: %f %%\n", float64(after.Idle-before.Idle)/total*100)
}

LICENSE

Copyright 2017-2019 Hatena Co., Ltd.

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.