Provided by: pcp_5.3.7-1_amd64 bug

NAME

       pmlogcheck - checks for invalid data in a PCP archive

SYNOPSIS

       pmlogcheck [-lmvwz?]  [-n pmnsfile] [-S start] [-T finish] [-Z timezone] archive

DESCRIPTION

       pmlogcheck prints information about the nature of any invalid data which it detects in the
       files of a PCP archive.

       The archive has the base  name  archive  and  must  have  been  previously  created  using
       pmlogger(1).

OPTIONS

       The available command line options are:

       -l, --label
            Print  the  archive  label, showing the log format version, the time and date for the
            start and (current) end of the archive, and  the  host  from  which  the  performance
            metrics values were collected.

       -m, --metadataonly
            Skip  Pass  3  (see  below)  and  only  check  the  archive  meta data.  This can run
            substantially faster in cases where the volume  data  doesn't  need  to  be  checked,
            especially on archives with compressed data volume(s).

       -n pmnsfile, --namespace=pmnsfile
            Load an alternative Performance Metrics Name Space (PMNS(5)) from the file pmnsfile.

       -S starttime, --start=starttime
            Specify  the  starttime of time window over which metrics should be checked in Pass 3
            (see below).  Refer to PCPIntro(1) for a  complete  description  of  the  syntax  for
            starttime.

       -T endtime, --finish=endtime
            Specify  the  endtime  of  time window over which metrics should be checked in Pass 3
            (see below).  Refer to PCPIntro(1) for a  complete  description  of  the  syntax  for
            endtime.

       -v, --verbose
            Enable verbose mode.

       -w, --nowrap
            Suppress reporting of counter wraps.

       -z, --hostzone
            Use  the  local  timezone  of  the host that is the source of the performance metrics
            archive.  The default is to use the timezone of the local host.

       -Z timezone, --timezone=timezone
            Use timezone for the date and time.  Timezone is in the  format  of  the  environment
            variable  TZ  as  described in environ(7).  The default is to use the timezone of the
            local host.

       -?, --help
            Display usage message and exit.

OPERATION

       The checking proceeds in a number of passes, each designed to validate progressively  more
       complex semantic relationships between the information in a PCP archive.

   Pass 0
       Each  physical  file of the PCP archive is processed to ensure the label records are valid
       and consistent, and that each file contains an integral number of  physical  records  with
       correct header and trailer fields.

       Any  errors  at  this stage are usually fatal.  The PCP archive is probably damaged beyond
       repair, and no more passes of pmlogcheck are attempted.

   Pass 1
       Validates the integrity of the temporal index, usually archive.index.

       As the temporal index is (strictly speaking) optional, errors at this stage are handled by
       marking the index as bad and ignoring it for the remainder of the pmlogcheck passes.

       Permanent  repair  can  be  achieved by removing the temporal index file and then making a
       copy of the PCP archive using pmlogrewrite(1) or pmlogextract(1).  This will create a  new
       temporal index for the copied archive as a side-effect.

   Pass 2
       Validates the integrity of the metadata file, usually archive.meta.

   Pass 3
       Validates  the integrity of each of the log volumes of the PCP archive, usually archive.0,
       archive.1, etc.

       There is some basic integrity checks to ensure the encoding  of  values  for  each  metric
       remains  consistent  and  the  values  are  well formed across all the observations in the
       archive.

       Also the timestamps for the observations are expected to be  monotonically  increasing  as
       the archive is tranversed.

       Additional   attention   is  given  to  counter  metrics  (type  from  pmLookupDesc(3)  is
       PM_SEM_COUNTER) which are expected to have monotonically increasing values.  If the values
       are  not  monotonic  increasing  this may suggest a counter wrap has happened or there has
       been some interruption or reset to the underlying source of the performance data  that  is
       no captured in the archive.

       For  each  counter  metric  which has been detected as having wrapped at some point in the
       archive, pmlogcheck produces output describing the metric name (with instance  identifiers
       where  appropriate),  the  internal  storage  type for the metric, the value of the metric
       before the counter wrap (with its associated timestamp), and the value of the metric after
       the wrap (also with a timestamp).

       The -w option may be used to suppress reporting of counter wraps.

       pmlogcheck  produces two different timestamp formats, depending on the interval over which
       it is run.  For an interval greater than 24 hours, the date is displayed  in  addition  to
       the  time  at which the counter wrap occurred.  If the extent of the data being checked is
       less than 24 hours, a more precise format is used  (time  is  displayed  with  millisecond
       precision, but without the date).

FILES

       $PCP_VAR_DIR/pmns/*
            default PMNS specification files

       $PCP_LOG_DIR/pmlogger/<hostname>
            default  directory  for  PCP  archives containing performance data collected from the
            host hostname.

PCP ENVIRONMENT

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

SEE ALSO

       PCPIntro(1), pmdumplog(1), pmlogextract(1), pmlogger(1), pmlogrewrite(1), pmlogsummary(1),
       pmLookupDesc(3), pcp.conf(5), pcp.env(5) and PMNS(5).