контейнер для метрики и всех ее значений (container for a metric and all its values)
Дубль
(статьи:
qmcmetric - контейнер для метрики и всех ее значений )
Имя (Name)
QmcMetric
- container for a metric and all its values
Синопсис C ++ (C++ synopsis)
#include <pcp/pmc/Metric.h>
CC ... -lpcp_pmc -lpcp
Описание (Description)
A QmcMetric
object is a container for a single metric and all its
values.
The QmcMetricValue
structure is used to hold the instance index,
values and errors of each instance. In the case of a singular
metric, a single QmcMetricValue
object is used.
A QmcMetric
object consists of a list of QmcMetricValue
objects,
indexes to the descriptors in the metric's QmcGroup
and
QmcContext
and flags to indicate if the instances are explicit or
implicit, and if only active metrics are required after
QmcMetric::updateIndom
is called.
Конструкторы (Constructors)
Metrics should be constructed through the QmcGroup::addMetric
methods as this will ensure that the references to the metric's
context, descriptor and instance domain are correctly
initialized.
INSTANCES
For metrics with an instance domain it is possible to add and
remove any instance, and also update the instance list to reflect
changes in a dynamic instance domain.
bool updateIndom();
Update the metric to include new instances. This method will
first call QmcContext::update
to update the instance domain.
If the active flag is set in the QmcGroup::addMetric
call,
only instances will exported by the metric, otherwise the
metric will export all instances listed in the domain.
The ordering of instances may change as a result of this
call. Instances that already existed will keep their current
and previous values and errors, even if they are in a
different order.
int addInst(QString const& name);
Add the instance name
to the metric. If the instance does
not exist in the instance domain, a PMAPI(3) error will be
returned. This method ignores the value of the active flag
set in the QmcMetric
constructor.
void removeInst(uint_t index);
Remove the instance at position index from the metric.
Диагностика (Diagnostic)
Error messages are generated using pmprintf(3) but are not
flushed. It is the responsibility of the user to call pmflush(3)
to output any messages.
Additional diagnostics may be activated by adding the option pmc
to the global debugging specification, as described in
pmSetDebug(3).
Смотри также (See also)
PMAPI(3), QMC(3), QMC_Context
(3), QMC_Group
(3), pmflush(3) and
pmprintf(3).