Function _disk_io

clients/client-psutil.py:238–292

the code is by: https://github.com/giampaolo/psutil/blob/master/scripts/iotop.py good luck for opensource! modify: cpp.la Calculate IO usage by comparing IO statics before and after the interval. Return a tuple including all currently running processes sorted by

()

        time.sleep(INTERVAL)

def _disk_io():
    """
    the code is by: https://github.com/giampaolo/psutil/blob/master/scripts/iotop.py
    good luck for opensource! modify: cpp.la
    Calculate IO usage by comparing IO statics before and
        after the interval.
        Return a tuple including all currently running processes
        sorted by IO activity and total disks I/O activity.
    磁盘IO：因为IOPS原因，SSD和HDD、包括RAID卡，ZFS等。IO对性能的影响还需要结合自身服务器情况来判断。
    比如我这里是机械硬盘，大量做随机小文件读写，那么很低的读写也就能造成硬盘长时间的等待。
    如果这里做连续性IO，那么普通机械硬盘写入到100Mb/s，那么也能造成硬盘长时间的等待。
    磁盘读写有误差：4k，8k ，https://stackoverflow.com/questions/34413926/psutil-vs-dd-monitoring-disk-i-o
    macos/win，暂不处理。
    """
    if "darwin" in sys.platform or "win" in sys.platform:
        diskIO["read"] = 0
        diskIO["write"] = 0
    else:
        while True:
            # first get a list of all processes and disk io counters
            procs = [p for p in psutil.process_iter()]
            for p in procs[:]:
                try:
                    p._before = p.io_counters()
                except psutil.Error:
                    procs.remove(p)
                    continue
            disks_before = psutil.disk_io_counters()

            # sleep some time, only when INTERVAL==1 , io read/write per_sec.
            # when INTERVAL > 1, io read/write per_INTERVAL
            time.sleep(INTERVAL)

            # then retrieve the same info again
            for p in procs[:]:
                with p.oneshot():
                    try:
                        p._after = p.io_counters()
                        p._cmdline = ' '.join(p.cmdline())
                        if not p._cmdline:
                            p._cmdline = p.name()
                        p._username = p.username()
                    except (psutil.NoSuchProcess, psutil.ZombieProcess):
                        procs.remove(p)
            disks_after = psutil.disk_io_counters()

            # finally calculate results by comparing data before and
            # after the interval
            for p in procs:
                p._read_per_sec = p._after.read_bytes - p._before.read_bytes
                p._write_per_sec = p._after.write_bytes - p._before.write_bytes
                p._total = p._read_per_sec + p._write_per_sec

            diskIO["read"] = disks_after.read_bytes - disks_before.read_bytes
            diskIO["write"] = disks_after.write_bytes - disks_before.write_bytes

def get_realtime_data():
    '''