com.datastax.driver.core.PerHostPercentileTracker Maven / Gradle / Ivy
/*
* Copyright DataStax, Inc.
*
* This software can be used solely with DataStax Enterprise. Please consult the license at
* http://www.datastax.com/terms/datastax-dse-driver-license-terms
*/
package com.datastax.driver.core;
/**
* A {@code PercentileTracker} that maintains a separate histogram for each host.
*
* This gives you per-host latency percentiles, meaning that each host will only be compared to
* itself.
*/
public class PerHostPercentileTracker extends PercentileTracker {
private PerHostPercentileTracker(
long highestTrackableLatencyMillis,
int numberOfSignificantValueDigits,
int minRecordedValues,
long intervalMs) {
super(
highestTrackableLatencyMillis,
numberOfSignificantValueDigits,
minRecordedValues,
intervalMs);
}
@Override
protected Host computeKey(Host host, Statement statement, Exception exception) {
return host;
}
/**
* Returns a builder to create a new instance.
*
* @param highestTrackableLatencyMillis the highest expected latency. If a higher value is
* reported, it will be ignored and a warning will be logged. A good rule of thumb is to set
* it slightly higher than {@link SocketOptions#getReadTimeoutMillis()}.
* @return the builder.
*/
public static Builder builder(long highestTrackableLatencyMillis) {
return new Builder(highestTrackableLatencyMillis);
}
/** Helper class to build {@code PerHostPercentileTracker} instances with a fluent interface. */
public static class Builder extends PercentileTracker.Builder {
Builder(long highestTrackableLatencyMillis) {
super(highestTrackableLatencyMillis);
}
@Override
protected Builder self() {
return this;
}
@Override
public PerHostPercentileTracker build() {
return new PerHostPercentileTracker(
highestTrackableLatencyMillis,
numberOfSignificantValueDigits,
minRecordedValues,
intervalMs);
}
}
}