1PMLOGCHECK(1) General Commands Manual PMLOGCHECK(1)
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6 pmlogcheck - checks for invalid data in a PCP archive
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9 pmlogcheck [-lmwz] [-n pmnsfile] [-S start] [-T finish] [-Z timezone]
10 archive
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13 pmlogcheck prints information about the nature of any invalid data
14 which it detects in the files of a PCP archive.
15 The archive has the base name archive and must have been previously
17 created using pmlogger(1).
18 Normally pmlogcheck operates on the default Performance Metrics Name
20 Space (PMNS(5)), however if the -n option is specified an alternative
21 namespace is loaded from the file pmnsfile.
22 The command line options -S and -T can be used to specify a time window
24 over which metrics should be checked in Pass 3 (see below). These
25 options are common to many Performance Co-Pilot tools and are fully
26 described in PCPIntro(1).
27 The -l option prints the archive label, showing the log format version,
29 the time and date for the start and (current) end of the archive, and
30 the host from which the performance metrics values were collected.
31 The -m option skips Pass 3 (see below) and only checks the archive meta
33 data. This can run substantially faster in cases where the volume data
34 doesn't need to be checked, especially on archives with compressed data
35 volume(s).
36 By default, pmlogcheck reports the time of day according to the local
38 timezone on the system where pmlogcheck is run. The -Z option changes
39 the timezone to timezone in the format of the environment variable TZ
40 as described in environ(7). The -z option changes the timezone to the
41 local timezone at the host that is the source of the performance met‐
42 rics, as specified in the label record of the archive log.
43 The checking proceeds in a number of passes, each designed to validate
45 progressively more complex semantic relationships between the informa‐
46 tion in a PCP archive.
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49 Each physical file of the PCP archive is processed to ensure the label
50 records are valid and consistent, and that each file contains an inte‐
51 gral number of physical records with correct header and trailer fields.
52 Any errors at this stage are usually fatal. The PCP archive is proba‐
54 bly damaged beyond repair, and no more passes of pmlogcheck are
55 attempted.
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58 Validates the integrity of the temporal index, usually archive.index.
59 As the temporal index is (strictly speaking) optional, errors at this
61 stage are handled by marking the index as bad and ignoring it for the
62 remainder of the pmlogcheck passes.
63 Permanent repair can be achieved by removing the temporal index file
65 and then making a copy of the PCP archive using pmlogrewrite(1) or
66 pmlogextract(1). This will create a new temporal index for the copied
67 archive as a side-effect.
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70 Validates the integrity of the metadata file, usually archive.meta.
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73 Validates the integrity of each of the log volumes of the PCP archive,
74 usually archive.0, archive.1, etc.
75 There is some basic integrity checks to ensure the encoding of values
77 for each metric remains consistent and the values are well formed
78 across all the observations in the archive.
79 Also the timestamps for the observations are expected to be monotoni‐
81 cally increasing as the archive is tranversed.
82 Additional attention is given to counter metrics (type from
84 pmLookupDesc(3) is PM_SEM_COUNTER) which are expected to have monotoni‐
85 cally increasing values. If the values are not monotonic increasing
86 this may suggest a counter wrap has happened or there has been some
87 interruption or reset to the underlying source of the performance data
88 that is no captured in the archive.
89 For each counter metric which has been detected as having wrapped at
91 some point in the archive, pmlogcheck produces output describing the
92 metric name (with instance identifiers where appropriate), the internal
93 storage type for the metric, the value of the metric before the counter
94 wrap (with its associated timestamp), and the value of the metric after
95 the wrap (also with a timestamp).
96 The -w option may be used to suppress reporting of counter wraps.
98 pmlogcheck produces two different timestamp formats, depending on the
100 interval over which it is run. For an interval greater than 24 hours,
101 the date is displayed in addition to the time at which the counter wrap
102 occurred. If the extent of the data being checked is less than 24
103 hours, a more precise format is used (time is displayed with millisec‐
104 ond precision, but without the date).
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107 $PCP_VAR_DIR/pmns/*
108 default PMNS specification files
109 $PCP_LOG_DIR/pmlogger/hostname
110 default directory for PCP archives containing performance
111 data collected from the host hostname.
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114 Environment variables with the prefix PCP_ are used to parameterize the
115 file and directory names used by PCP. On each installation, the file
116 /etc/pcp.conf contains the local values for these variables. The
117 $PCP_CONF variable may be used to specify an alternative configuration
118 file, as described in pcp.conf(5).
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121 PCPIntro(1), pmdumplog(1), pmlogextract(1), pmlogger(1), pmlo‐
122 grewrite(1), pmlogsummary(1), pmval(1), pmLookupDesc(3), pcp.conf(5),
123 pcp.env(5) and PMNS(5).
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126 All are generated on standard error and are intended to be self-
127 explanatory.
128Performance Co-Pilot PCP PMLOGCHECK(1)