Linux系统性能监控--CPU、内存、磁盘I/O、网咯I/O--基于psutil库

1. psutil简介

• psutil是一个开源切跨平台的库，其提供了便利的函数用来获取才做系统的信息，比如CPU，内存，磁盘，网络等。此外，psutil还可以用来进行进程管理，包括判断进程是否存在、获取进程列表、获取进程详细信息等。
• psutil是一个跨平台的库，在官方网站上查到其支持如下操作系统。
  • Linux
  • Windows
  • OSX
  • FreeBSD
  • OpenBSD
  • NetBSD
  • Sun Solaris
  • AIX
• psutil包含了异常、类、功能函数和常量，其中功能函数用来获取系统的信息，如CPU、磁盘、内存、网络等。类用来实现进程的管理功能

  2. psutil安装

  $ pip install psutil

3. psutil使用

1. 获取CPU信息

>>> import psutil
>>> psutil.cpu_count()     # CPU逻辑数量
4
>>> psutil.cpu_count(logical=False)     # CPU物理核心
4
>>> psutil.cpu_times()      # CPU时间  
scputimes(user=1.92, nice=0.0, system=4.64, idle=297.77, iowait=0.56, irq=0.0, softirq=0.0, steal=0.0, guest=0.0)

2. 获取内存信息

>>> import psutil
>>> psutil.virtual_memory()    # 总内存/可用内存/内存使用率/已用内存/空闲内存
svmem(total=16926494720, available=10762715136, percent=36.4, used=6163779584, free=10762715136)

3. 获取磁盘信息

>>> import psutil
>>> psutil.disk_partitions()         # 磁盘分区信息
[sdiskpart(device='/dev/mapper/vg_tony-lv_root', mountpoint='/', fstype='ext4', opts='rw'), sdiskpart(device='/dev/sda1', mountpoint='/boot', fstype='ext4', opts='rw')]
>>> psutil.disk_usage('/')         # 磁盘使用情况
sdiskusage(total=18569568256, used=1994440704, free=15631831040, percent=11.3)
>>> psutil.disk_io_counters()         # 磁盘IO
sdiskio(read_count=6118, write_count=897, read_bytes=107744256, write_bytes=5440512, read_time=3123, write_time=367, read_merged_count=1704, write_merged_count=432, busy_time=1984)

4. 获取网络信息

>>> import psutil
>>> psutil.net_io_counters()     # 获取网络读写字节/包的个数
snetio(bytes_sent=23277, bytes_recv=134908, packets_sent=226, packets_recv=1865, errin=0, errout=0, dropin=0, dropout=0)
>>> psutil.net_if_addrs()     # 获取网络接口信息
{
'lo': [*****], 
'eth0': [****)]
}
>>> psutil.net_if_stats()     # 获取网络接口状态
{
'lo': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_UNKNOWN: 0>, speed=0, mtu=16436), 
'eth0': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_FULL: 2>, speed=1000, mtu=1500)
}

4. psutil实例

利用psutil功能获取系统资源信息

import psutil
def cpu_info():
    print_str = ''
    print_str += "当前系统cpu使用情况:\n"
    cpu_per = []
    cpu_user = []
    cpu_nice = []
    cpu_system = []
    cpu_idle = []
    cpu_iowait = []
    cpu_irq = []
    cpu_softirq = []
    cpu_steal = []
    cpu_guest = []
    count = 3
    while count > 0:
        cpu_status = psutil.cpu_times()
        cpu_per.append(psutil.cpu_percent(interval=2))
        cpu_user.append(cpu_status.user)
        cpu_nice.append(cpu_status.nice)
        cpu_system.append(cpu_status.system)
        cpu_idle.append(cpu_status.idle)
        cpu_iowait.append(cpu_status.iowait)
        cpu_irq.append(cpu_status.irq)
        cpu_softirq.append(cpu_status.softirq)
        cpu_steal.append(cpu_status.steal)
        cpu_guest.append(cpu_status.guest)
        count -= 1
    print_str += ("   cpu利用率 = " + str(round(sum(cpu_per)/3, 2)) + "%\n")
    print_str += ("   user = " + str(round(sum(cpu_user)/3, 2)) + "\n")
    print_str += ("   nice = " + str(round(sum(cpu_nice)/3, 2)) + "\n")
    print_str += ("   system = " + str(round(sum(cpu_system)/3, 2)) + "\n")
    print_str += ("   idle = " + str(round(sum(cpu_idle)/3, 2)) + "\n")
    print_str += ("   iowait = " + str(round(sum(cpu_iowait)/3, 2)) + "\n")
    print_str += ("   irq = " + str(round(sum(cpu_irq)/3, 2)) + "\n")
    print_str += ("   softirq = " + str(round(sum(cpu_softirq)/3, 2)) + "\n")
    print_str += ("   steal = " + str(round(sum(cpu_steal)/3, 2)) + "\n")
    print_str += ("   guest = " + str(round(sum(cpu_guest)/3, 2)) + "\n")
    print_str += "************\n"
    return print_str
def mem_info():
       print_str = ""
       mem_total = []
       mem_ava = []
       mem_per = []
       mem_free = []
       mem_ava_per = []
       count = 3
       while count > 0:
              mem = psutil.virtual_memory()
              mem_total.append(mem.total)
              mem_ava.append(mem.available)
              mem_per.append(mem.percent)
              mem_free.append(mem.free)
              mem_ava_per.append(mem.available*100 / mem.total)
              count -= 1
       bytes_M = 1024 * 1024
       print_str += '当前系统内存使用情况：\n'
       print_str += '   总内存：%sM \n' % round(sum(mem_total)/3/bytes_M, 2)
       print_str += '   可用内存：%sM \n' % round(sum(mem_ava)/3/bytes_M, 2)
       print_str += '   已使用（占比）：%s%s \n' % (sum(mem_per)/3, '%')
       print_str += '   剩余内存：%sM\n' % round(sum(mem_free)/3/bytes_M, 2)
       percent_ava = round((sum(mem_ava)/3 * 100) / (sum(mem_total)/3), 1)
       if percent_ava >= 20:
              print_str += '   当前系统可用内存充足,清放心使用!\n'
       else:
              print_str += '   当前系统可用内存不足,请注意！\n'
       print_str += ('   当前系统可用内存百分比：' + str(percent_ava) + '%\n')
       if psutil.swap_memory().percent <= 0.7:
              print_str += '   虚拟内存空间使用率良好.\n'
       else:
              print_str += '   当前虚拟内存使用超出规定上限，请注意！\n'
       print_str += ('   当前系统的SWAP交换空间(虚拟内存)利用率为：' + str(psutil.swap_memory().percent) + '%\n')
       print_str += '************\n'
       return print_str
def bytes2human(n):
    symbols = ("K", "M", "G", "T", "P", "E", "Z", "Y")
    prefix = {}
    for i,s in enumerate(symbols):
        prefix[s] = 1 << (i + 1) * 10
    for s in reversed(symbols):
        if n >= prefix[s]:
            value = float(n) / prefix[s]
            return "%.1f%s" % (value, s)
    return "%sB" % n
def get_dist_info():
    disk_total = []
    disk_uesd = []
    disk_free = []
    disk_precent = []
    count = 3
    while count > 0:
        disk_usage = psutil.disk_usage("/")
        disk_total.append(disk_usage.total)
        disk_uesd.append(disk_usage.used)
        disk_free.append(disk_usage.free)
        disk_precent.append(disk_usage.percent)
        count -= 1
    print_str = "当前系统磁盘使用情况:\n"
    print_str += ("   磁盘总量 = " + bytes2human(sum(disk_total)/3) + "\n")
    print_str += ("   磁盘使用 = " + bytes2human(sum(disk_uesd)/3) + "\n")
    print_str += ("   磁盘剩余 = " + bytes2human(sum(disk_free)/3) + "\n")
    print_str += ("   磁盘使用率 = " + str(sum(disk_precent)/3) + "%\n")
    print_str += "************\n"
    return print_str
def write_log(print_info):
    time_str = time.strftime("%Y-%m-%d", time.localtime())
    file_name = "./" + time_str + ".log"
    if  not os.path.exists(file_name):
        os.mknod(file_name)
        with open(file_name, "w") as f:
            f.write(print_info)
    else:
        with open(file_name, "a") as f:
            f.write(print_info)
if __name__ == '__main__':
    now_time = time.strftime('%H:%M:%S', time.localtime(time.time()))
    cpu = cpu_info.cpu_info()
    mem = mem_info.mem_info()
    disk = disk_io_info.get_dist_info()
    print_total = "*******************************\n" + now_time + '\n' + cpu + mem + disk
    write_log(print_total)