com.nsysmon.measure.scalar

Interface AScalarMeasurer

All Superinterfaces:

AShutdownable

All Known Implementing Classes:

AConnectionCounter, ACpuUtilizationMeasurer, AJmxGcMeasurer, AJmxMemMeasurer, AJmxTomcatDeltaMeasurer, AJmxTomcatMeasurer, AProcDiskstatsMeasurer, AProcNetDevMeasurer, AProcSelfStatMeasurer, ASystemLoadMeasurer, CpuTotalAndUserMeasurer, SystemLoadOneMinuteMeasurer, ThreadingMeasurer

public interface AScalarMeasurer
extends AShutdownable

Scalar measurements are performed in two steps because some data (e.g. CPU load) must be calculated based on raw data from two distinct points in time. Things like 'load' is inherently an average over some period of time, after all.

So first, prepareMeasurements() is called, allowing a measurer to store some data as a memento (e.g. the first number of jiffies together with the first timestamp).

Then the caller waits some time, typically between a tenth of a second and a second, but potentially longer, to give measurers a solid time base to average data over.

Finally, contributeMeasurements() is called, passing in the mementos of the preparation phase. This is when the actual data is collected. Non-averaging measurers can (and probably should) ignore prepareMeasurements() and the entire memento mechanism.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	AScalarMeasurer.EvaluatedValue

Field Summary

Fields

Modifier and Type	Field and Description
static String	KEY_CONFIGURATION_ACTIVE
static String	KEY_CONFIGURATION_HIGH
static String	KEY_CONFIGURATION_MEDIUM

Method Summary

Modifier and Type	Method and Description
void	contributeMeasurements(Map<String,AScalarDataPoint> data, long timestamp, Map<String,Object> mementos)
default List<String>	getConfigurationParameters()
default String	getDescriptionOfMeasurement(String measurement)
default String	getGroupnameOfMeasurement(String measurement)
com.ajjpj.afoundation.collection.immutable.AOption<Long>	getTimeoutInMilliSeconds()
void	prepareMeasurements(Map<String,Object> mementos)

Methods inherited from interface com.nsysmon.util.AShutdownable

shutdown

Field Detail

KEY_CONFIGURATION_ACTIVE

static final String KEY_CONFIGURATION_ACTIVE

See Also:

Constant Field Values

KEY_CONFIGURATION_MEDIUM

static final String KEY_CONFIGURATION_MEDIUM

See Also:

Constant Field Values

KEY_CONFIGURATION_HIGH

static final String KEY_CONFIGURATION_HIGH

See Also:

Constant Field Values

Method Detail

prepareMeasurements

void prepareMeasurements(Map<String,Object> mementos)
                  throws Exception

Throws:

Exception

contributeMeasurements

void contributeMeasurements(Map<String,AScalarDataPoint> data,
                            long timestamp,
                            Map<String,Object> mementos)
                     throws Exception

Throws:

Exception

getTimeoutInMilliSeconds

com.ajjpj.afoundation.collection.immutable.AOption<Long> getTimeoutInMilliSeconds()

getGroupnameOfMeasurement

default String getGroupnameOfMeasurement(String measurement)

getDescriptionOfMeasurement

default String getDescriptionOfMeasurement(String measurement)

getConfigurationParameters

default List<String> getConfigurationParameters()