службы обнаружения асинхронного архива и содержимого (asynchronous archive location and contents discovery services)
Дубль
(статьи:
pmDiscoverClose - службы обнаружения асинхронного архива и содержимого )
Имя (Name)
pmDiscoverSetup, pmDiscoverSetSlots, pmDiscoverSetEventLoop,
pmDiscoverSetConfiguration, pmDiscoverSetMetricRegistry,
pmDiscoverClose - asynchronous archive location and contents
discovery services
Синопсис C (C Synopsis)
#include <pcp/pmwebapi.h>
int pmDiscoverSetup(pmDiscoverModule *module, pmDiscoverCallBacks
*callbacks, void *arg);
int pmDiscoverSetSlots(pmDiscoverModule *module, void *slots);
int pmDiscoverSetEventLoop(pmDiscoverModule *module, void
*uvloop);
int pmDiscoverSetConfiguration(pmDiscoverModule *module, struct
dict *config);
int pmDiscoverSetMetricRegistry(pmDiscoverModule *module, struct
mmv_registry *registry);
int pmDiscoverClose(pmDiscoverModule *module);
cc ... -lpcp_web
Описание (Description)
The pmDiscoverSetup and related functions are an integral part of
the libpcp_web API library, as used by and described in
pmwebapi(3), pmproxy(1), pmseries(1) and elsewhere. These
functions provide an asynchronous event driven mechanism to
automatically discover PCP archives created by pmlogger(1) and
any other application capable of writing PCP archives. This
includes pmrep(1) and other applications using the LOGIMPORT(3)
API for importing performance data into the PCP infrastructure
and writing PCP archives.
The pmDiscover API services dynamically discover, monitor and
manage directories of PCP archives as they are created, written
to, compressed and eventually deleted. The underlying archive
life-cycle is normally managed by the PCP log management
infrustructure (see pmlogger_daily(1)). Discovered archives that
are active (currently being written) are "log-tailed" to extract
near live/real-time performance data which is then passed off via
registered callbacks for further processing. Archives that are
compressed or inactive are tracked/monitored but not log-tailed.
The pmDiscover routines can be configured to automatically
discover and monitor PCP archives in one or more directories as
specified in the pmDiscoverModule, which is initially set up by
calling pmDiscoverSetConfiguration to create a module of type
pmDiscoverModule, as described above. The resulting module is
then passed to pmDiscoverSetup along with an initialized
structure of callbacks of type pmDiscoverCallBacks.
Setting up a discovery module and callbacks would normally
declare an instance of pmDiscoverSettings, e.g.
#include <pcp/pmwebapi.h>
static pmDiscoverSettings someapp_discover = {
.callbacks.on_source = pmSomeappDiscoverSource,
.callbacks.on_closed = pmSomeappDiscoverClosed,
.callbacks.on_labels = pmSomeappDiscoverLabels,
.callbacks.on_metric = pmSomeappDiscoverMetric,
.callbacks.on_values = pmSomeappDiscoverValues,
.callbacks.on_indom = pmSomeappDiscoverInDom,
.callbacks.on_text = pmSomeappDiscoverText,
.module.on_info = someapp_logging_function,
};
And then initialize this with API calls similar to the following:
pmDiscoverSetEventLoop(&someapp_discover.module, myevents);
pmDiscoverSetConfiguration(&someapp_discover.module, myconfig);
pmDiscoverSetMetricRegistry(&someapp_discover.module, metric_registry);
pmDiscoverSetup(&someapp_discover.module, &someapp_discover.callbacks, &privatedata);
The above code must then implement each of the declared callbacks
etc. to do whatever is required with the data passed in to the
callback. Prototypes for these callbacks can be found in the
pmwebapi.h header. The callbacks will be made asynchronously, as
archives are discovered or deleted and as new data is written to
active archive log volume and metadata files.
In the case of pmproxy(1), callbacks are registered to capture
performance data, which is then sent to redis(1) as the database
back-end for fast scalable time-series queries by clients of the
PMWEBAPI(3) REST API services. Such clients include the
pmseries(1) application and pmproxy(1), which is the back-end
REST API server for grafana-pcp, a native grafana-server(1) data-
source for PCP.
Диагностика (Diagnostic)
Generally zero on success, or on error a negative return code,
see pmerr(1).
Файлы (Files)
The default archive directory is $PCP_LOG_DIR, which is normally
/var/log/pcp/pmlogger. The API recursively descends all sub-
directories and also dynamically discovers any new directories or
archives found therein.
Смотри также (See also)
grafana-server(1), pmerr(1), pmlogger(1), pmproxy(1),
pmseries(1), PMWEBAPI(3), mmv_stats_registry(3), PMAPI(3),
pmErrStr(3), pcp.conf(5) and pcp.env(5).
