com.mysql.cj.jdbc.ha.plugins.failover

Class ClusterAwareMetrics

java.lang.Object

com.mysql.cj.jdbc.ha.plugins.failover.ClusterAwareMetrics

public class ClusterAwareMetrics
extends java.lang.Object

Collect certain performance metrics for ClusterAwareConnectionProxy.

Performance (duration in time) metrics: - Failover Detection Duration of time between a start of executing sql statement to the moment when driver identifies a communication error and starts a failover process (a process to re-connect to another cluster instance). - Writer Failover Procedure Duration of time running writer failover procedure. - Reader Failover Procedure Duration of time running reader failover procedure.

Performance (hit-miss) metrics: - Successful Failover Reconnects A total number of failover events vs a number of successful ones - Used Last Connected Reader Number of time driver utilises details about a last successfully connected reader host. Knowing the last successfully connected reader host helps driver to connect to this host in the first turn rather than trying to randomly connect to any reader hosts. This metric is applicable for read-only connections only. - Invalid Initial Connection As a side-effect of using last connected reader host from a cache, there's a chance that this host may turn out to be a writer, not a reader as expected. In such a case, driver has to drop connection to this host since it's not accurate and initiate a new one to another host. Such cases are measured by this metric. "Hit" event corresponds to dropping connection and connecting to another host. - Used Cached Topology Number of time driver utilises a cached cluster topology

Constructor Summary

Constructors

Constructor and Description
ClusterAwareMetrics()

Method Summary

Modifier and Type	Method and Description
void	registerFailoverConnects(boolean isHit)
void	registerFailureDetectionTime(long timeMs)
void	registerInvalidInitialConnection(boolean isHit)
void	registerReaderFailoverProcedureTime(long timeMs)
void	registerUseCachedTopology(boolean isHit)
void	registerUseLastConnectedReader(boolean isHit)
void	registerWriterFailoverProcedureTime(long timeMs)
void	reportMetrics(Log log) Report metrics.

Methods inherited from class java.lang.Object

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

Constructor Detail

ClusterAwareMetrics

public ClusterAwareMetrics()

Method Detail

registerFailureDetectionTime

public void registerFailureDetectionTime(long timeMs)

registerWriterFailoverProcedureTime

public void registerWriterFailoverProcedureTime(long timeMs)

registerReaderFailoverProcedureTime

public void registerReaderFailoverProcedureTime(long timeMs)

registerFailoverConnects

public void registerFailoverConnects(boolean isHit)

registerInvalidInitialConnection

public void registerInvalidInitialConnection(boolean isHit)

registerUseLastConnectedReader

public void registerUseLastConnectedReader(boolean isHit)

registerUseCachedTopology

public void registerUseCachedTopology(boolean isHit)

reportMetrics

public void reportMetrics(Log log)

Report metrics.