Package org.apache.iotdb.confignode.manager.load.cache.detector

Class PhiAccrualDetector

java.lang.Object

org.apache.iotdb.confignode.manager.load.cache.detector.PhiAccrualDetector

All Implemented Interfaces:

IFailureDetector

public class PhiAccrualDetector
extends Object
implements IFailureDetector

The Phi Failure Detector, proposed by Hayashibara, Naohiro, et al. "The/spl phi/accrual failure detector.". It is an accrual approach based on heartbeat history analysis with dynamic sensitivity and tunable threshold. It is adaptive with early failure detection, increased accuracy and improved system stability.

Initially, Phi has a cold start period where it will only collect heartbeat samples and fallback decision-making to FixedDetector. After collecting enough samples, it will start failure detection using the Phi algo.

Field Summary

Fields inherited from interface org.apache.iotdb.confignode.manager.load.cache.IFailureDetector

FIXED_DETECTOR, PHI_ACCRUAL_DETECTOR

Constructor Summary

Constructors

Constructor	Description
PhiAccrualDetector(long threshold, long acceptableHeartbeatPauseNs, long minHeartbeatStdNs, int minimalSampleCount, IFailureDetector fallbackDuringColdStart)

Method Summary

Modifier and Type	Method	Description
boolean	isAvailable(List<AbstractHeartbeatSample> history)	Given the heartbeat history, decide whether this endpoint is still available

Methods inherited from class java.lang.Object

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

Constructor Details

PhiAccrualDetector

public PhiAccrualDetector(long threshold,
 long acceptableHeartbeatPauseNs,
 long minHeartbeatStdNs,
 int minimalSampleCount,
 IFailureDetector fallbackDuringColdStart)

Method Details

isAvailable

public boolean isAvailable(List<AbstractHeartbeatSample> history)

Description copied from interface: IFailureDetector

Given the heartbeat history, decide whether this endpoint is still available

Specified by:

isAvailable in interface IFailureDetector

Parameters:

history - heartbeat history

Returns:

false if the endpoint is under failure