org.apache.hadoop.fs

Class DU

java.lang.Object

org.apache.hadoop.util.Shell

org.apache.hadoop.fs.DU

@InterfaceAudience.LimitedPrivate(value={"HDFS","MapReduce"})
@InterfaceStability.Evolving
public class DU
extends Shell

Filesystem disk space usage statistics. Uses the unix 'du' program

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.util.Shell

Shell.ExitCodeException, Shell.ShellCommandExecutor

Field Summary

Fields inherited from class org.apache.hadoop.util.Shell

isSetsidAvailable, LINK_COMMAND, LINUX, LOG, READ_LINK_COMMAND, SET_GROUP_COMMAND, SET_OWNER_COMMAND, SET_PERMISSION_COMMAND, timeOutInterval, TOKEN_SEPARATOR_REGEX, USER_NAME_COMMAND, WINDOWS, WindowsProcessLaunchLock, WINUTILS

Constructor Summary

Constructors

Constructor and Description
DU(File path, Configuration conf) Keeps track of disk usage.
DU(File path, long interval) Keeps track of disk usage.

Method Summary

Methods

Modifier and Type	Method and Description
void	decDfsUsed(long value) Decrease how much disk space we use.
String	getDirPath()
protected String[]	getExecString() return an array containing the command name & its parameters
long	getUsed()
void	incDfsUsed(long value) Increase how much disk space we use.
static void	main(String[] args)
protected void	parseExecResult(BufferedReader lines) Parse the execution result
protected void	run() Override to hook in DUHelper class.
void	shutdown() Shut down the refreshing thread.
void	start() Start the disk usage checking thread.
String	toString()

Methods inherited from class org.apache.hadoop.util.Shell

appendScriptExtension, appendScriptExtension, execCommand, execCommand, execCommand, getCheckProcessIsAliveCommand, getEnvironmentVariableRegex, getExitCode, getGetPermissionCommand, getGroupsCommand, getGroupsForUserCommand, getHadoopHome, getProcess, getQualifiedBinPath, getReadlinkCommand, getRunScriptCommand, getSetOwnerCommand, getSetPermissionCommand, getSetPermissionCommand, getSignalKillCommand, getSymlinkCommand, getUsersForNetgroupCommand, getWinUtilsPath, isJava7OrAbove, isTimedOut, setEnvironment, setWorkingDirectory

Methods inherited from class java.lang.Object

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

Constructor Detail

DU

public DU(File path,
  long interval)
   throws IOException

Keeps track of disk usage.

Parameters:

path - the path to check disk usage in

interval - refresh the disk usage at this interval

Throws:

IOException - if we fail to refresh the disk usage

DU

public DU(File path,
  Configuration conf)
   throws IOException

Keeps track of disk usage.

Parameters:

path - the path to check disk usage in

conf - configuration object

Throws:

IOException - if we fail to refresh the disk usage

Method Detail

decDfsUsed

public void decDfsUsed(long value)

Decrease how much disk space we use.

Parameters:

value - decrease by this value

incDfsUsed

public void incDfsUsed(long value)

Increase how much disk space we use.

Parameters:

value - increase by this value

getUsed

public long getUsed()
             throws IOException

Returns:

disk space used

Throws:

IOException - if the shell command fails

getDirPath

public String getDirPath()

Returns:

the path of which we're keeping track of disk usage

run

protected void run()
            throws IOException

Override to hook in DUHelper class. Maybe this can be used more generally as well on Unix/Linux based systems

Overrides:

run in class Shell

Throws:

IOException

start

public void start()

Start the disk usage checking thread.

shutdown

public void shutdown()

Shut down the refreshing thread.

toString

public String toString()

Overrides:

toString in class Object

getExecString

protected String[] getExecString()

Description copied from class: Shell

return an array containing the command name & its parameters

Specified by:

getExecString in class Shell

parseExecResult

protected void parseExecResult(BufferedReader lines)
                        throws IOException

Description copied from class: Shell

Parse the execution result

Specified by:

parseExecResult in class Shell

Throws:

IOException

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception