Question

我在python中使用rrdtool库。同一个python脚本每天返回数据，但现在突然它返回了生成元组内的None对象。 rrd文件尚未修改。返回的类型是元组，甚至是rrdinfo，如果被打印出来的话。请花一些时间来查看它。

    import sys
    import pprint
    sys.path.append('/opt/plexus-srv/rrdtool-1.4.9/lib64/python2.6/site-
    packages')
    import rrdtool
    rrd_file = sys.argv[1]
    rrd_info = rrdtool.info(rrd_file)

    data = rrdtool.fetch(rrd_file,"AVERAGE")
    print(type(data))
    pp = pprint.PrettyPrinter(indent =4)
    pp.pprint(data)
    pp.pprint(rrd_info)

输出是：

    <type 'tuple'>
('sum',)
1510142400
[(None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,), (None,)]
     {   'ds[sum].index': 0L,
    'ds[sum].last_ds': '99.3',
    'ds[sum].max': None,
    'ds[sum].min': None,
    'ds[sum].minimal_heartbeat': 120L,
    'ds[sum].type': 'GAUGE',
    'ds[sum].unknown_sec': 0L,
    'ds[sum].value': 1290.8999999999999,
    'filename': '/home/u43555766/aad/plexus/rrdsample/testing/cpu/cpu_idle.rrd',
    'header_size': 1416L,
    'last_update': 1510030543L,
    'rra[0].cdp_prep[0].unknown_datapoints': 0L,
    'rra[0].cdp_prep[0].value': None,
    'rra[0].cf': 'AVERAGE',
    'rra[0].cur_row': 49L,
    'rra[0].pdp_per_row': 1L,
    'rra[0].rows': 490L,
    'rra[0].xff': 0.5,
    'rra[1].cdp_prep[0].unknown_datapoints': 0L,
    'rra[1].cdp_prep[0].value': 198.78666666666669,
    'rra[1].cf': 'AVERAGE',
    'rra[1].cur_row': 2264L,
    'rra[1].pdp_per_row': 4L,
    'rra[1].rows': 2890L,
    'rra[1].xff': 0.5,
    'rra[2].cdp_prep[0].unknown_datapoints': 0L,
    'rra[2].cdp_prep[0].value': 198.78666666666669,
    'rra[2].cf': 'AVERAGE',
    'rra[2].cur_row': 873L,
    'rra[2].pdp_per_row': 20L,
    'rra[2].rows': 2026L,
    'rra[2].xff': 0.5,
    'rra[3].cdp_prep[0].unknown_datapoints': 0L,
    'rra[3].cdp_prep[0].value': 22058.293333333328,
    'rra[3].cf': 'AVERAGE',
    'rra[3].cur_row': 387L,
    'rra[3].pdp_per_row': 240L,
    'rra[3].rows': 754L,
    'rra[3].xff': 0.5,
    'rra[4].cdp_prep[0].unknown_datapoints': 0L,
    'rra[4].cdp_prep[0].value': 117354.74000000028,
    'rra[4].cf': 'AVERAGE',
    'rra[4].cur_row': 214L,
    'rra[4].pdp_per_row': 5760L,
    'rra[4].rows': 375L,
    'rra[4].xff': 0.5,
    'rrd_version': '0003',
    'step': 15L}

Answer 1

这个问题最明显的答案是没有数据可以返回。

您没有说明是否以及如何将数据添加到RRD文件。由于您的'fetch'调用没有任何参数来指定分辨率，开始或结束，因此它可能会以5分钟的分辨率获得默认的一天，现在结束。你确实有一个RRA匹配，但我们不知道那里是否有任何数据。

查看您提供的数据，似乎您在1510142400时运行fetch，但RRD上次更新时间为1510030543，大约提前31小时。可能最后一天没有数据？

尝试从命令行运行'rrdtool fetch'和'rrdtool dump'，并验证是否存储了数据，并确保它们是您想到的时间。也许可以将其他参数传递给'fetch'来指定step，start和end。

Answer 2

我是rrdtool的新手所以没有意识到我错过了收集数据的开始时间。几天前，这些文件来自服务器。缺少获取命令＆＃39; -s＆＃39;时间因此打印无对象。添加＆＃39; -s＆＃39;用＆＃39; -96h＆＃39;打印数据。感谢@ steve-shipway

rrdtool fetch返回None对象

2 个答案: