Python-解析（FIO）JSON输出

Question

我有Linux fio命令的json输出，如下所示，我将解析诸如字典之类的值，并从某些键中提取某些值。 但是此json输出的嵌套层将输出打包为KVP中的巨大“值”。 关于如何更好地解析这些嵌套数据结构的任何技巧？

{
  "disk_util": [
    {
      "aggr_util": 96.278308,
      "in_queue": 247376,
      "write_ticks": 185440,
      "read_ticks": 61924,
      "write_merges": 0,
      "read_merges": 0,
      "write_ios": 240866,
      "read_ios": 18257,
      "name": "dm-0",
      "util": 97.257058,
      "aggr_read_ios": 18465,
      "aggr_write_ios": 243642,
      "aggr_read_merges": 1,
      "aggr_write_merge": 72,
      "aggr_read_ticks": 62420,
      "aggr_write_ticks": 185796,
      "aggr_in_queue": 245504
    },
    {
      "util": 96.278308,
      "name": "sda",
      "read_ios": 18465,
      "write_ios": 243642,
      "read_merges": 1,
      "write_merges": 72,
      "read_ticks": 62420,
      "write_ticks": 185796,
      "in_queue": 245504
    }
  ],
  "jobs": [
    {
      "latency_window": 0,
      "latency_percentile": 100,
      "latency_target": 0,
      "latency_depth": 64,
      "latency_ms": {
        ">=2000": 0,
        "2000": 0,
        "1000": 0,
        "750": 0,
        "2": 0,
        "4": 0,
        "10": 0,
        "20": 0,
        "50": 0,
        "100": 0,
        "250": 0,
        "500": 0
      },
      "latency_us": {
        "1000": 0,
        "750": 0,
        "2": 0,
        "4": 0,
        "10": 0,
        "20": 0,
        "50": 0,
        "100": 0,
        "250": 0,
        "500": 0
      },
      "write": {
        "iops_samples": 35,
        "iops_stddev": 1608.115728,
        "iops_mean": 13835.571429,
        "iops_max": 16612,
        "iops_min": 9754,
        "bw_samples": 35,
        "drop_ios": 0,
        "short_ios": 0,
        "total_ios": 243678,
        "runtime": 17611,
        "iops": 13836.692976,
        "bw": 55346,
        "io_kbytes": 974712,
        "io_bytes": 998105088,
        "slat_ns": {
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "clat_ns": {
          "percentile": {
            "0.00": 0
          },
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "lat_ns": {
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "bw_min": 39016,
        "bw_max": 66448,
        "bw_agg": 99.994218,
        "bw_mean": 55342.8,
        "bw_dev": 6432.427333
      },
      "read": {
        "iops_samples": 35,
        "iops_stddev": 126.732776,
        "iops_mean": 1048.257143,
        "iops_max": 1336,
        "iops_min": 772,
        "bw_samples": 35,
        "drop_ios": 0,
        "short_ios": 0,
        "total_ios": 18466,
        "runtime": 17611,
        "iops": 1048.549202,
        "bw": 4194,
        "io_kbytes": 73864,
        "io_bytes": 75636736,
        "slat_ns": {
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "clat_ns": {
          "percentile": {
            "0.00": 0
          },
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "lat_ns": {
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "bw_min": 3088,
        "bw_max": 5344,
        "bw_agg": 99.993188,
        "bw_mean": 4193.714286,
        "bw_dev": 506.844597
      },
      "job options": {
        "rwmixread": "7",
        "rw": "randrw",
        "size": "1G",
        "iodepth": "64",
        "bs": "4k",
        "filename": "test",
        "name": "test"
      },
      "elapsed": 18,
      "eta": 0,
      "error": 0,
      "groupid": 0,
      "jobname": "test",
      "trim": {
        "iops_samples": 0,
        "iops_stddev": 0,
        "iops_mean": 0,
        "iops_max": 0,
        "iops_min": 0,
        "bw_samples": 0,
        "drop_ios": 0,
        "short_ios": 0,
        "total_ios": 0,
        "runtime": 0,
        "iops": 0,
        "bw": 0,
        "io_kbytes": 0,
        "io_bytes": 0,
        "slat_ns": {
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "clat_ns": {
          "percentile": {
            "0.00": 0
          },
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "lat_ns": {
          "stddev": 0,
          "mean": 0,
          "max": 0,
          "min": 0
        },
        "bw_min": 0,
        "bw_max": 0,
        "bw_agg": 0,
        "bw_mean": 0,
        "bw_dev": 0
      },
      "usr_cpu": 11.447391,
      "sys_cpu": 74.680597,
      "ctx": 28972,
      "majf": 0,
      "minf": 31,
      "iodepth_level": {
        ">=64": 99.975967,
        "32": 0.1,
        "16": 0.1,
        "8": 0.1,
        "4": 0.1,
        "2": 0.1,
        "1": 0.1
      },
      "latency_ns": {
        "1000": 0,
        "750": 0,
        "2": 0,
        "4": 0,
        "10": 0,
        "20": 0,
        "50": 0,
        "100": 0,
        "250": 0,
        "500": 0
      }
    }
  ],
  "global options": {
    "gtod_reduce": "1",
    "direct": "1",
    "ioengine": "libaio",
    "randrepeat": "1"
  },
  "time": "Sat Oct 14 23:18:28 2017",
  "timestamp_ms": 1508023108010,
  "timestamp": 1508023108,
  "fio version": "fio-3.1"
}

我实际上是从一个文件中导入它：

import json

my_file = open('fio.json', 'r')
my_dict = json.load(my_file)

for k, v in my_dict.items():
    print("Key: {0}, value: {1}").format(k, v)

但是，当进行迭代时，它将使所有嵌套表和字典返回被忽略的输出，例如

Key: disk_util, value: [{u'aggr_write_ticks': 185796, u'write_merges': 0, u'write_ticks': 185440, u'write_ios': 240866, u'aggr_write_ios': 243642, u'aggr_read_ticks': 62420, u'read_ios': 18257, u'util': 97.257058, u'read_ticks': 61924, u'aggr_write_merge': 72, u'read_merges': 0, u'aggr_in_queue': 245504, u'aggr_read_ios': 18465, u'aggr_util': 96.278308, u'aggr_read_merges': 1, u'in_queue': 247376, u'name': u'dm-0'}, {u'read_merges': 1, u'name': u'sda', u'write_ios': 243642, u'read_ios': 18465, u'util': 96.278308, u'read_ticks': 62420, u'write_merges': 72, u'in_queue': 245504, u'write_ticks': 185796}]

Answer 1

json.load（）维护json文件类型。

您似乎有语法错误。

位置错误) 。

import json


my_file = open('fio.json', 'r')
my_dict = json.load(my_file)

for index, key in enumerate(my_dict):
    print("Key: {0}, value: {1}".format(key, my_dict[key]))