Section 3: library functions
pmTypeStr, pmTypeStr_r – convert a performance metric type into a string C Synopsis #include <pcp/pmapi.h> const char *pmTypeStr(int type); char *pmTypeStr_r(int type, char *buf, int buflen); cc … -lpcp Description Given a performance metric type, pmTypeStr produces a terse ASCII equivalent, appropriate for use in error and diagnostic messages. The pmTypeStr_r function does the same,…
pmTrimNameSpace – prune a performance metrics name space C Synopsis #include <pcp/pmapi.h> int pmTrimNameSpace(void); cc … -lpcp Description In some (rare) cases it is helpful to prune the Performance Metrics Name Space (PMNS) to match the available metrics. The default PMNS that is accessible to a Performance Metrics Application Programming Interface (PMAPI) client is provided…
pmTraversePMNS, pmTraversePMNS_r – traverse the performance metrics name space C Synopsis #include <pcp/pmapi.h> int pmTraversePMNS(const char *name, void (*dometric)(const char *)); int pmTraversePMNS_r(const char *name, void (*dometric_r)(const char *, void *), void *closure); cc … -lpcp Description The routine pmTraversePMNS may be used to perform a depth-first traversal of the Performance Metrics Name Space (PMNS)….
pmtime, pmTimeConnect, pmTimeDisconnect, pmTimeRecv, pmTimeSendAck, pmTimeShowDialog – time control functions for synchronizing the archive position and update interval between one or more applications C Synopsis #include <pcp/pmtime.h> int pmTimeConnect(int port, pmTime *state); int pmTimeDisconnect(int fd); int pmTimeSendAck(int fd, struct timeval *fetchTime); int pmTimeShowDialog(int fd, int show); int pmTimeRecv(int fd, pmTime *state); cc … -lpcp_gui Description…
pmStore – modify values of performance metrics C Synopsis #include <pcp/pmapi.h> int pmStore(const pmResult *result); cc … -lpcp Description In some special cases it may be helpful to modify the current values of performance metrics, e.g. to reset a counter to zero, or to modify a “metric” which is a control variable for some agent…
pmSortInstances – sort performance metric values on instance identifier C Synopsis #include <pcp/pmapi.h> void pmSortInstances(pmResult *result); cc … -lpcp Description The routine pmSortInstances may be used to guarantee that for each performance metric in the result from pmFetch(3), the instances are in ascending instance identifier sequence. This is most useful when trying to compute rates…
pmSetMode – set collection time parameters for the current PMAPI context C Synopsis #include <pcp/pmapi.h> int pmSetMode(int mode, const struct timeval *when, int delta); cc … -lpcp Description pmSetMode is used to define the collection time and/or mode for accessing performance metrics and meta-data in the current Performance Metrics Application Programming Interface (PMAPI) context. This…
pmRegisterDerived, pmRegisterDerivedMetric – register a derived metric name and definition C Synopsis #include <pcp/pmapi.h> char *pmRegisterDerived(char *name, char *expr); int pmRegisterDerivedMetric(char *name, char *expr, char **errmsg); cc … -lpcp Description Derived metrics provide a way of extending the Performance Metrics Name Space (PMNS) with new metrics defined at the PCP client-side using arithmetic expressions over…
pmafm, pmRecordSetup, pmRecordAddHost, pmRecordControl – record mode support for PMAPI clients C Synopsis #include <pcp/pmafm.h> FILE *pmRecordSetup(const char *folio, const char *creator, int replay); int pmRecordAddHost(const char *host, int isdefault, pmRecordHost **rhp); int pmRecordControl(pmRecordHost *rhp, int request, const char *options); cc … -lpcp_gui Description These routines may be used to create a Performance Co-Pilot (PCP) archive “on the…
pmReconnectContext – reconnect to a PMAPI context C Synopsis #include <pcp/pmapi.h> int pmReconnectContext(int handle); cc … -lpcp Description As a consequence of network, host or Performance Metrics Collector Daemon (PMCD) failures, an application’s connection to a PMCD may be established and then subsequently lost. The routine pmReconnectContext allows an application to request that the context…
pmPrintValue – print a performance metric value C Synopsis #include <stdio.h> #include <pcp/pmapi.h> void pmPrintValue(FILE *f, int valfmt, int type, const pmValue *val, int minwidth); cc … -lpcp Description The value of a single performance metric (as identified by val) is printed on the standard I/O stream identified by f. The value of the performance metric is…
pmParseUnitsStr – parse time point specification C Synopsis #include <pcp/pmapi.h> int pmParseUnitsStr(const char *string, struct pmUnits *out, double *outMult, char **errMsg); cc … -lpcp Description pmParseUnitsStr is designed to encapsulate the interpretation of a unit/scale specification in command line switches for use by the PCP client tools. This function expects to be called with the unit/scale specification as…
pmParseTimeWindow – parse time window command line arguments C Synopsis #include <pcp/pmapi.h> int pmParseTimeWindow(const char *swStart, const char *swEnd, const char *swAlign, const char *swOffset, const struct timeval *logStart, const struct timeval *logEnd, struct timeval *rsltStart, struct timeval *rsltEnd, struct timeval *rsltOffset, char **errMsg); cc … -lpcp Description pmParseTimeWindow is designed to encapsulate the interpretation of the -S, -T, -A and -O command line…
pmParseInterval – convert interval string to timeval structure C Synopsis #include <pcp/pmapi.h> int pmParseInterval(const char *string, struct timeval *rslt, char **errmsg); cc … -lpcp Description pmParseInterval parses the argument string specifying an interval of time and fills in the tv_sec and tv_usec components of the rslt structure to represent that interval. The input string is most…
pmNumberStr, pmNumberStr_r – fixed width output format for numbers C Synopsis #include <pcp/pmapi.h> const char *pmNumberStr(double value); char *pmNumberStr_r(double value, char *buf, int buflen); cc … -lpcp Description pmNumberStr returns the address of a 8-byte buffer that holds a null-byte terminated representation of value suitable for output with fixed width fields. The pmNumberStr_r function does…
pmNewZone – establish a reporting timezone C Synopsis #include <pcp/pmapi.h> int pmNewZone(const char *tz); cc … -lpcp Description The current reporting timezone affects the timezone used by pmCtime(3) and pmLocaltime(3). The argument tz defines a timezone string, in the format described for the TZ environment variable, see environ(7). pmNewZone sets the current reporting timezone, and…
pmNewContextZone – establish a reporting timezone based on a PMAPI context C Synopsis #include <pcp/pmapi.h> int pmNewContextZone(void); cc … -lpcp Description The current reporting timezone affects the timezone used by pmCtime(3) and pmLocaltime(3). If the current PMAPI context is an archive, pmNewContextZone uses the timezone from the archive label record to set the current reporting…
pmNewContext – establish a new PMAPI context C Synopsis #include <pcp/pmapi.h> int pmNewContext(int type, const char *name); cc … -lpcp Description An application using the Performance Metrics Application Programming Interface (PMAPI) may manipulate several concurrent contexts, each associated with a source of performance metrics, e.g. pmcd(1) on some host, or a set of archive logs…
pmNameInDomArchive – translate an instance identifier into an instance name C Synopsis #include <pcp/pmapi.h> int pmNameInDomArchive(pmInDom indom, int inst, char **name); cc … -lpcp Description Provided that the current Performance Metrics Application Programming Interface (PMAPI) context is associated with a set of archive logs, pmNameInDomArchive will scan the union of all the instance domain metadata…
pmNameInDom – translate an instance identifier into an instance name C Synopsis #include <pcp/pmapi.h> int pmNameInDom(pmInDom indom, int inst, char **name); cc … -lpcp Description For the instance domain indom, in the current Performance Metrics Application Programming Interface (PMAPI) context, locate the instance with the internal instance identifier given by inst, and return the full…