1PMLOGCHECK(1)               General Commands Manual              PMLOGCHECK(1)
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NAME

6       pmlogcheck - checks for invalid data in a PCP archive
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SYNOPSIS

9       pmlogcheck  [-lmvwz?]   [-n  pmnsfile] [-S start] [-T finish] [-Z time‐
10       zone] archive
11

DESCRIPTION

13       pmlogcheck prints information about the  nature  of  any  invalid  data
14       which it detects in the files of a PCP archive.
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16       The  archive  has  the  base name archive and must have been previously
17       created using pmlogger(1).
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OPTIONS

20       The available command line options are:
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22       -l, --label
23            Print the archive label, showing the archive format  version,  the
24            time  and date for the start and (current) end of the archive, and
25            the host from which the performance metrics values were collected.
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27       -m, --metadataonly
28            Skip Pass 3 (see below) and only  check  the  archive  meta  data.
29            This  can  run substantially faster in cases where the volume data
30            doesn't need to be checked, especially on archives with compressed
31            data volume(s).
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33       -n pmnsfile, --namespace=pmnsfile
34            Load  an alternative Performance Metrics Name Space (PMNS(5)) from
35            the file pmnsfile.
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37       -S starttime, --start=starttime
38            Specify the starttime of time window over which metrics should  be
39            checked  in  Pass  3 (see below).  Refer to PCPIntro(1) for a com‐
40            plete description of the syntax for starttime.
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42       -T endtime, --finish=endtime
43            Specify the endtime of time window over which  metrics  should  be
44            checked  in  Pass  3 (see below).  Refer to PCPIntro(1) for a com‐
45            plete description of the syntax for endtime.
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47       -v, --verbose
48            Enable verbose mode.
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50       -w, --nowrap
51            Suppress reporting of counter wraps.
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53       -z, --hostzone
54            Use the local timezone of the host that is the source of the  per‐
55            formance  metrics  archive.  The default is to use the timezone of
56            the local host.
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58       -Z timezone, --timezone=timezone
59            Use timezone for the date and time.  Timezone is in the format  of
60            the  environment  variable TZ as described in environ(7).  The de‐
61            fault is to use the timezone of the local host.
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63       -?, --help
64            Display usage message and exit.
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OPERATION

67       The checking proceeds in a number of passes, each designed to  validate
68       progressively  more complex semantic relationships between the informa‐
69       tion in a PCP archive.
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71   Pass 0
72       Each physical file of the PCP archive is processed to ensure the  label
73       records  are valid and consistent, and that each file contains an inte‐
74       gral number of physical records with correct header and trailer fields.
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76       Any errors at this stage are usually fatal.  The PCP archive is  proba‐
77       bly  damaged  beyond  repair,  and no more passes of pmlogcheck are at‐
78       tempted.
79
80   Pass 1
81       Validates the integrity of the temporal index, usually archive.index.
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83       As the temporal index is (strictly speaking) optional, errors  at  this
84       stage  are  handled by marking the index as bad and ignoring it for the
85       remainder of the pmlogcheck passes.
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87       Permanent repair can be achieved by removing the  temporal  index  file
88       and  then making a copy of the PCP archive using pmlogrewrite(1) or pm‐
89       logextract(1).  This will create a new temporal index  for  the  copied
90       archive as a side-effect.
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92   Pass 2
93       Validates the integrity of the metadata file, usually archive.meta.
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95   Pass 3
96       Validates the integrity of each of the volumes of the PCP archive, usu‐
97       ally archive.0, archive.1, etc.
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99       There is some basic integrity checks to ensure the encoding  of  values
100       for  each  metric  remains  consistent  and  the values are well formed
101       across all the observations in the archive.
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103       Also the timestamps for the observations are expected to  be  monotoni‐
104       cally increasing as the archive is tranversed.
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106       Additional  attention  is  given  to  counter  metrics  (type  from pm‐
107       LookupDesc(3) is PM_SEM_COUNTER) which are expected to  have  monotoni‐
108       cally  increasing  values.   If the values are not monotonic increasing
109       this may suggest a counter wrap has happened or there has been some in‐
110       terruption  or  reset  to the underlying source of the performance data
111       that is no captured in the archive.
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113       For each counter metric which has been detected as  having  wrapped  at
114       some  point  in  the archive, pmlogcheck produces output describing the
115       metric name (with instance identifiers where appropriate), the internal
116       storage type for the metric, the value of the metric before the counter
117       wrap (with its associated timestamp), and the value of the metric after
118       the wrap (also with a timestamp).
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120       The -w option may be used to suppress reporting of counter wraps.
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122       pmlogcheck  produces  two different timestamp formats, depending on the
123       interval over which it is run.  For an interval greater than 24  hours,
124       the date is displayed in addition to the time at which the counter wrap
125       occurred.  If the extent of the data being  checked  is  less  than  24
126       hours,  a more precise format is used (time is displayed with millisec‐
127       ond precision, but without the date).
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FILES

130       $PCP_VAR_DIR/pmns/*
131            default PMNS specification files
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133       $PCP_LOG_DIR/pmlogger/<hostname>
134            default directory for PCP  archives  containing  performance  data
135            collected from the host hostname.
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PCP ENVIRONMENT

138       Environment variables with the prefix PCP_ are used to parameterize the
139       file and directory names used by PCP.  On each installation,  the  file
140       /etc/pcp.conf  contains  the  local  values  for  these variables.  The
141       $PCP_CONF variable may be used to specify an alternative  configuration
142       file, as described in pcp.conf(5).
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SEE ALSO

145       PCPIntro(1),    pmdumplog(1),   pmlogextract(1),   pmlogger(1),   pmlo‐
146       grewrite(1), pmlogsummary(1), pmLookupDesc(3), pcp.conf(5),  pcp.env(5)
147       and PMNS(5).
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