alluxio.master.meta

Class JournalSpaceMonitor

java.lang.Object

alluxio.master.meta.JournalSpaceMonitor

All Implemented Interfaces:

HeartbeatExecutor, Closeable, AutoCloseable

public class JournalSpaceMonitor
extends Object
implements HeartbeatExecutor

A heartbeat executor which periodically tracks the amount of disk space available for a particular path, generally the disk holding the journal. This monitor is only applicable to systems which are running on the Linux OS and which are running the embedded journal. Other configurations are invalid. Running this monitor on such systems is undefined behavior.

Constructor Summary

Constructors

Constructor and Description
JournalSpaceMonitor(AlluxioConfiguration configuration) Convenience method for JournalSpaceMonitor(String, long).
JournalSpaceMonitor(String journalPath, long warnCapacityPercentThreshold)

Method Summary

Modifier and Type	Method and Description
void	close() Cleans up any resources used by the heartbeat executor.
protected List<JournalDiskInfo>	getDiskInfo() Gets the current disk information from the system for the journal path.
List<String>	getJournalDiskWarnings()
void	heartbeat(long timeLimitMs) Implements the heartbeat logic.

Methods inherited from class java.lang.Object

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

Constructor Detail

JournalSpaceMonitor

public JournalSpaceMonitor(AlluxioConfiguration configuration)

Convenience method for JournalSpaceMonitor(String, long).

Parameters:

configuration - the current alluxio configuration

JournalSpaceMonitor

public JournalSpaceMonitor(String journalPath,
                           long warnCapacityPercentThreshold)

Parameters:

journalPath - the path to the journal location

warnCapacityPercentThreshold - when a device utilization falls below this threshold, emit warnings to the log

Method Detail

getDiskInfo

protected List<JournalDiskInfo> getDiskInfo()
                                     throws IOException

Gets the current disk information from the system for the journal path.

Returns:

a list of the disks that back the journal path. Many systems will just have one disk. Depending on the configuration multiple disks may back the journal path, in which case we report information on all of them

Throws:

IOException - when obtaining the disk information fails

getJournalDiskWarnings

public List<String> getJournalDiskWarnings()

Returns:

a list warning messages that can be logged or displayed to the user in the UI

heartbeat

public void heartbeat(long timeLimitMs)
               throws InterruptedException

Description copied from interface: HeartbeatExecutor

Implements the heartbeat logic.

Specified by:

heartbeat in interface HeartbeatExecutor

Parameters:

timeLimitMs - time limit in milliseconds this heartbeat should not exceed when running

Throws:

InterruptedException - if the thread is interrupted

close

public void close()

Description copied from interface: HeartbeatExecutor

Cleans up any resources used by the heartbeat executor.

Specified by:

close in interface HeartbeatExecutor

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable