org.opennms.netmgt.timeseries.sampleread

Class TimeseriesFetchStrategy

java.lang.Object

org.opennms.netmgt.timeseries.sampleread.TimeseriesFetchStrategy

All Implemented Interfaces:

MeasurementFetchStrategy

public class TimeseriesFetchStrategy
extends Object
implements MeasurementFetchStrategy

Used to retrieve measurements from TimeSeriesStorage. If a request to fetch(long, long, long, int, java.lang.Long, java.lang.Long, java.util.List<org.opennms.netmgt.measurements.model.Source>, boolean) spans multiple resources, separate calls to the TimeSeriesStorage will be performed in parallel. Reading the samples and computing the aggregated values can be very CPU intensive. The "parallelism" attribute is used to set an upper limit on how may concurrent threads can be used to perform these calculations. By default, this is set to the number of cores, but can be reduced if the operator wishes to ensure cores are available for other purposes.

Author:

jwhite

Field Summary

Fields

Modifier and Type	Field and Description
static int	PARALLELISM

Constructor Summary

Constructors

Constructor and Description
TimeseriesFetchStrategy()

Method Summary

Modifier and Type	Method and Description
FetchResults	fetch(long start, long end, long step, int maxrows, Long interval, Long heartbeat, List<Source> sources, boolean relaxed) Fetches the measurements for the given sources.
protected void	setMetricRegistry(com.codahale.metrics.MetricRegistry registry)
protected void	setResourceDao(ResourceDao resourceDao)
protected void	setTimeseriesStorageManager(TimeseriesStorageManager timeseriesStorage)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

PARALLELISM

public static final int PARALLELISM

Constructor Detail

TimeseriesFetchStrategy

public TimeseriesFetchStrategy()

Method Detail

fetch

public FetchResults fetch(long start,
                          long end,
                          long step,
                          int maxrows,
                          Long interval,
                          Long heartbeat,
                          List<Source> sources,
                          boolean relaxed)

Description copied from interface: MeasurementFetchStrategy

Fetches the measurements for the given sources.

Specified by:

fetch in interface MeasurementFetchStrategy

Parameters:

start - timestamp in milliseconds

end - timestamp in milliseconds

step - desired resolution in milliseconds - actual resolution might differ

maxrows - maximum number of rows - no limit when <= 0

interval - duration in milliseconds, used by strategies that implement late aggregation

heartbeat - duration in milliseconds, used by strategies that implement late aggregation

sources - array of sources - these should have unique labels

relaxed - if false a missing source results in a return of null. true on the other hand ignores that source.

Returns:

null when a resource id or attribute cannot be found

setResourceDao

@Inject
protected void setResourceDao(ResourceDao resourceDao)

setTimeseriesStorageManager

@Inject
protected void setTimeseriesStorageManager(TimeseriesStorageManager timeseriesStorage)

setMetricRegistry

@Inject
protected void setMetricRegistry(@Named(value="timeseriesMetricRegistry")
                                         com.codahale.metrics.MetricRegistry registry)