com.datastax.driver.core

Class QueryLogger.DynamicThresholdQueryLogger

java.lang.Object

com.datastax.driver.core.QueryLogger

com.datastax.driver.core.QueryLogger.DynamicThresholdQueryLogger

All Implemented Interfaces:

LatencyTracker

Enclosing class:

QueryLogger

@Beta
public static class QueryLogger.DynamicThresholdQueryLogger
extends QueryLogger

A QueryLogger that uses a dynamic threshold in milliseconds to track slow queries.

Dynamic thresholds are based on per-host latency percentiles, as computed by PerHostPercentileTracker.

This class is currently provided as a beta preview: it hasn't been extensively tested yet, and the API is still subject to change.

Nested Class Summary

Nested classes/interfaces inherited from class com.datastax.driver.core.QueryLogger

QueryLogger.Builder, QueryLogger.ConstantThresholdQueryLogger, QueryLogger.DynamicThresholdQueryLogger

Field Summary

Fields inherited from class com.datastax.driver.core.QueryLogger

cluster, DEFAULT_MAX_LOGGED_PARAMETERS, DEFAULT_MAX_PARAMETER_VALUE_LENGTH, DEFAULT_MAX_QUERY_STRING_LENGTH, DEFAULT_SLOW_QUERY_THRESHOLD_MS, DEFAULT_SLOW_QUERY_THRESHOLD_PERCENTILE, ERROR_LOGGER, maxLoggedParameters, maxParameterValueLength, maxQueryStringLength, NORMAL_LOGGER, SLOW_LOGGER

Method Summary

Modifier and Type	Method and Description
PerHostPercentileTracker	getPerHostPercentileLatencyTracker() Return the PerHostPercentileTracker instance to use for recording per-host latency histograms.
double	getSlowQueryLatencyThresholdPercentile() Return the threshold percentile beyond which queries are considered 'slow' and logged as such by the driver.
protected void	maybeLogNormalOrSlowQuery(Host host, Statement statement, long latencyMs)
protected void	maybeLogSlowQuery(Host host, Statement statement, long latencyMs, long threshold)
void	setPerHostPercentileLatencyTracker(PerHostPercentileTracker perHostPercentileLatencyTracker) Set the PerHostPercentileTracker instance to use for recording per-host latency histograms.
void	setSlowQueryLatencyThresholdPercentile(double slowQueryLatencyThresholdPercentile) Set the threshold percentile beyond which queries are considered 'slow' and logged as such by the driver.

Methods inherited from class com.datastax.driver.core.QueryLogger

append, append, appendParameters, appendParameters, builder, countBoundValues, getMaxLoggedParameters, getMaxParameterValueLength, getMaxQueryStringLength, logQuery, maybeLogErrorQuery, maybeLogNormalQuery, onRegister, onUnregister, parameterValueAsString, parameterValueAsString, setMaxLoggedParameters, setMaxParameterValueLength, setMaxQueryStringLength, statementAsString, update

Methods inherited from class java.lang.Object

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

Method Detail

getPerHostPercentileLatencyTracker

public PerHostPercentileTracker getPerHostPercentileLatencyTracker()

Return the PerHostPercentileTracker instance to use for recording per-host latency histograms. Cannot be null.

Returns:

the PerHostPercentileTracker instance to use.

setPerHostPercentileLatencyTracker

public void setPerHostPercentileLatencyTracker(PerHostPercentileTracker perHostPercentileLatencyTracker)

Set the PerHostPercentileTracker instance to use for recording per-host latency histograms. Cannot be null.

Parameters:

perHostPercentileLatencyTracker - the PerHostPercentileTracker instance to use.

Throws:

IllegalArgumentException - if perHostPercentileLatencyTracker == null.

getSlowQueryLatencyThresholdPercentile

public double getSlowQueryLatencyThresholdPercentile()

Return the threshold percentile beyond which queries are considered 'slow' and logged as such by the driver. The default value is QueryLogger.DEFAULT_SLOW_QUERY_THRESHOLD_PERCENTILE.

Returns:

threshold percentile beyond which queries are considered 'slow' and logged as such by the driver.

setSlowQueryLatencyThresholdPercentile

public void setSlowQueryLatencyThresholdPercentile(double slowQueryLatencyThresholdPercentile)

Set the threshold percentile beyond which queries are considered 'slow' and logged as such by the driver.

Parameters:

slowQueryLatencyThresholdPercentile - Slow queries threshold percentile. It must be comprised between 0 inclusive and 100 exclusive.

Throws:

IllegalArgumentException - if slowQueryLatencyThresholdPercentile < 0 || slowQueryLatencyThresholdPercentile >= 100.

maybeLogNormalOrSlowQuery

protected void maybeLogNormalOrSlowQuery(Host host,
                                         Statement statement,
                                         long latencyMs)

Specified by:

maybeLogNormalOrSlowQuery in class QueryLogger

maybeLogSlowQuery

protected void maybeLogSlowQuery(Host host,
                                 Statement statement,
                                 long latencyMs,
                                 long threshold)