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pmgetarchivelabel(3) [centos man page]

PMGETARCHIVELABEL(3)					     Library Functions Manual					      PMGETARCHIVELABEL(3)

NAME
pmGetArchiveLabel - fetch the label record from a performance metrics archive log C SYNOPSIS
#include <pcp/pmapi.h> int pmGetArchiveLabel(pmLogLabel *lp); cc ... -lpcp DESCRIPTION
Within the framework of the Performance Co-Pilot (PCP), archive logs of performance metrics values may be accumulated and saved using the program pmlogger(1). The routine pmGetArchiveLabel may be used to fetch the label record from an archive log that has already been opened using pmNewContext(3), or pmDupContext(3), and thereby associated with the current Performance Metrics Application Programming Interface (PMAPI) context. The result returned via the pointer lp is a structure that must be pre-allocated by the caller and has the following format (defined in pmapi.h). /* * Label Record at the start of every log file */ typedef struct { int ll_magic; /* PM_LOG_MAGIC | log format version no. */ pid_t ll_pid; /* PID of logger */ struct timeval ll_start;/* start of this log */ char ll_hostname[PM_LOG_MAXHOSTLEN]; /* name of collection host */ char ll_tz[40]; /* $TZ at collection host */ } pmLogLabel; For an application, the most useful information from the archive label is likely to be in the fields ll_start, ll_hostname or ll_tz. Note that the size of the ll_hostname field is PM_LOG_MAXHOSTLEN (64 bytes) which is less than MAXHOSTNAMELEN (see gethostbyname(3)) on some platforms. These semantics are necessary to retain backwards compatibility with the PCP archive file format. pmGetArchiveLabel returns zero for success. 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 configura- tion file, as described in pcp.conf(5). Values for these variables may be obtained programmatically using the pmGetConfig(3) function. SEE ALSO
pmlogger(1), PMAPI(3), pmDupContext(3), pmGetConfig(3), pmNewContext(3), pcp.conf(5) and pcp.env(5). DIAGNOSTICS
PM_ERR_NOCONTEXT the current PMAPI context is either invalid, or not associated with an archive log Performance Co-Pilot PCP PMGETARCHIVELABEL(3)

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PMLOGCHECK(1)						      General Commands Manual						     PMLOGCHECK(1)

NAME
pmlogcheck - checks for invalid data in a PCP archive SYNOPSIS
pmlogcheck [-lz] [-n pmnsfile] [-S start] [-T finish] [-Z timezone] archive DESCRIPTION
pmlogcheck prints information about the nature of any invalid data which it detects in a PCP archive. Of particular interest are wrapped values for metrics which are expected to have monotonically increasing values. The archive has the base name archive and must have been previously created using pmlogger(1). Normally pmlogcheck operates on the default Performance Metrics Namespace (pmns(5)), however if the -n option is specified an alternative namespace is loaded from the file pmnsfile. The command line options -S and -T can be used to specify a time window over which metrics should be summarized. These options are common to many Performance Co-Pilot tools and are fully described in PCPIntro(1). The -l option prints 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. By default, pmlogcheck reports the time of day according to the local timezone on the system where pmlogcheck is run. The -Z option changes the timezone to timezone in the format of the environment variable TZ as described in environ(5). The -z option changes the time- zone to the local timezone at the host that is the source of the performance metrics, as specified in the label record of the archive log. OUTPUT FORMAT
For each metric having ``counter'' semantics (i.e. the metric is expected to increase monotonically) 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). 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 configura- tion file, as described in pcp.conf(5). SEE ALSO
PCPIntro(1), pmdumplog(1), pmlogextract(1), pmlogger(1), pmlogmerge(1), pmlogsummary(1), pmval(1), pcp.conf(5), pcp.env(5) and pmns(5). DIAGNOSTICS
All are generated on standard error and are intended to be self- explanatory. Performance Co-Pilot PCP PMLOGCHECK(1)

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