org.apache.hadoop.mapred

Class TaskLog

java.lang.Object

org.apache.hadoop.mapred.TaskLog

public class TaskLog
extends Object

A simple logger to handle the task-specific user logs. This class uses the system property hadoop.log.dir. This class is for Map/Reduce internal use only.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TaskLog.LogName The filter for userlogs.

Field Summary

Fields

Modifier and Type	Field and Description
static org.apache.hadoop.fs.PathFilter	USERLOGS_PATH_FILTER Path filter that filters out userlogs directory.

Constructor Summary

Constructors

Constructor and Description
TaskLog()

Method Summary

Methods

Modifier and Type	Method and Description
static String	addCommand(List<String> cmd, boolean isExecutable) Add quotes to each of the command strings and return as a single string
static List<String>	captureDebugOut(List<String> cmd, File debugoutFilename) Wrap a command in a shell to capture debug script's stdout and stderr to debugout.
static List<String>	captureOutAndError(List<String> cmd, File stdoutFilename, File stderrFilename, long tailLength) Wrap a command in a shell to capture stdout and stderr to files.
static List<String>	captureOutAndError(List<String> setup, List<String> cmd, File stdoutFilename, File stderrFilename, long tailLength) Wrap a command in a shell to capture stdout and stderr to files.
static List<String>	captureOutAndError(List<String> setup, List<String> cmd, File stdoutFilename, File stderrFilename, long tailLength, boolean useSetsid) Wrap a command in a shell to capture stdout and stderr to files.
static List<String>	captureOutAndError(List<String> setup, List<String> cmd, File stdoutFilename, File stderrFilename, long tailLength, boolean useSetsid, String pidFileName) Deprecated. pidFiles are no more used. Instead pid is exported to env variable JVM_PID.
static List<String>	captureOutAndError(List<String> setup, List<String> cmd, File stdoutFilename, File stderrFilename, long tailLength, String pidFileName) Deprecated. pidFiles are no more used. Instead pid is exported to env variable JVM_PID.
static void	createTaskAttemptLogDir(TaskAttemptID taskID, boolean isCleanup, String[] localDirs) Create log directory for the given attempt.
static File	getJobDir(JobID jobid) Get the user log directory for the job jobid.
static File	getJobDir(String jobid) Get the user log directory for the job jobid.
static String	getTaskAttemptLogDir(TaskAttemptID taskID, String cleanupSuffix, String[] localDirs) Get attempt log directory path for the given attempt-id under randomly selected mapred local directory.
static File	getTaskLogFile(TaskAttemptID taskid, boolean isCleanup, TaskLog.LogName filter)
static long	getTaskLogLength(JobConf conf) Get the desired maximum length of task's logs.
static File	getUserLogDir()
static void	syncLogs(String logLocation, TaskAttemptID taskid, boolean isCleanup, boolean segmented)

Methods inherited from class java.lang.Object

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

Field Detail

USERLOGS_PATH_FILTER

public static final org.apache.hadoop.fs.PathFilter USERLOGS_PATH_FILTER

Path filter that filters out userlogs directory.

Constructor Detail

TaskLog

public TaskLog()

Method Detail

createTaskAttemptLogDir

public static void createTaskAttemptLogDir(TaskAttemptID taskID,
                           boolean isCleanup,
                           String[] localDirs)
                                    throws IOException

Create log directory for the given attempt. This involves creating the following and setting proper permissions for the new directories
{hadoop.log.dir}/userlogs/
{hadoop.log.dir}/userlogs//
{one of the mapred-local-dirs}/userlogs/
{one of the mapred-local-dirs}/userlogs//

Parameters:

taskID - attempt-id for which log dir is to be created

isCleanup - Is this attempt a cleanup attempt ?

localDirs - mapred local directories

Throws:

IOException

getTaskAttemptLogDir

public static String getTaskAttemptLogDir(TaskAttemptID taskID,
                          String cleanupSuffix,
                          String[] localDirs)
                                   throws IOException

Get attempt log directory path for the given attempt-id under randomly selected mapred local directory.

Parameters:

taskID - attempt-id for which log dir path is needed

cleanupSuffix - ".cleanup" if this attempt is a cleanup attempt

localDirs - mapred local directories

Returns:

target task attempt log directory

Throws:

IOException

getTaskLogFile

public static File getTaskLogFile(TaskAttemptID taskid,
                  boolean isCleanup,
                  TaskLog.LogName filter)

syncLogs

public static void syncLogs(String logLocation,
            TaskAttemptID taskid,
            boolean isCleanup,
            boolean segmented)
                     throws IOException

Throws:

IOException

getTaskLogLength

public static long getTaskLogLength(JobConf conf)

Get the desired maximum length of task's logs.

Parameters:

conf - the job to look in

Returns:

the number of bytes to cap the log files at

captureOutAndError

public static List<String> captureOutAndError(List<String> cmd,
                              File stdoutFilename,
                              File stderrFilename,
                              long tailLength)
                                       throws IOException

Wrap a command in a shell to capture stdout and stderr to files. If the tailLength is 0, the entire output will be saved.

Parameters:

cmd - The command and the arguments that should be run

stdoutFilename - The filename that stdout should be saved to

stderrFilename - The filename that stderr should be saved to

tailLength - The length of the tail to be saved.

Returns:

the modified command that should be run

Throws:

IOException

captureOutAndError

public static List<String> captureOutAndError(List<String> setup,
                              List<String> cmd,
                              File stdoutFilename,
                              File stderrFilename,
                              long tailLength)
                                       throws IOException

Wrap a command in a shell to capture stdout and stderr to files. Setup commands such as setting memory limit can be passed which will be executed before exec. If the tailLength is 0, the entire output will be saved.

Parameters:

setup - The setup commands for the execed process.

cmd - The command and the arguments that should be run

stdoutFilename - The filename that stdout should be saved to

stderrFilename - The filename that stderr should be saved to

tailLength - The length of the tail to be saved.

Returns:

the modified command that should be run

Throws:

IOException

captureOutAndError

@Deprecated
public static List<String> captureOutAndError(List<String> setup,
                                         List<String> cmd,
                                         File stdoutFilename,
                                         File stderrFilename,
                                         long tailLength,
                                         String pidFileName)
                                       throws IOException

Deprecated. pidFiles are no more used. Instead pid is exported to env variable JVM_PID.

Wrap a command in a shell to capture stdout and stderr to files. Setup commands such as setting memory limit can be passed which will be executed before exec. If the tailLength is 0, the entire output will be saved.

Parameters:

setup - The setup commands for the execed process.

cmd - The command and the arguments that should be run

stdoutFilename - The filename that stdout should be saved to

stderrFilename - The filename that stderr should be saved to

tailLength - The length of the tail to be saved.

Returns:

the modified command that should be run

Throws:

IOException

captureOutAndError

@Deprecated
public static List<String> captureOutAndError(List<String> setup,
                                         List<String> cmd,
                                         File stdoutFilename,
                                         File stderrFilename,
                                         long tailLength,
                                         boolean useSetsid,
                                         String pidFileName)
                                       throws IOException

Deprecated. pidFiles are no more used. Instead pid is exported to env variable JVM_PID.

Wrap a command in a shell to capture stdout and stderr to files. Setup commands such as setting memory limit can be passed which will be executed before exec. If the tailLength is 0, the entire output will be saved.

Parameters:

setup - The setup commands for the execed process.

cmd - The command and the arguments that should be run

stdoutFilename - The filename that stdout should be saved to

stderrFilename - The filename that stderr should be saved to

tailLength - The length of the tail to be saved.

useSetsid - Should setsid be used in the command or not.

Returns:

the modified command that should be run

Throws:

IOException

captureOutAndError

public static List<String> captureOutAndError(List<String> setup,
                              List<String> cmd,
                              File stdoutFilename,
                              File stderrFilename,
                              long tailLength,
                              boolean useSetsid)
                                       throws IOException

Wrap a command in a shell to capture stdout and stderr to files. Setup commands such as setting memory limit can be passed which will be executed before exec. If the tailLength is 0, the entire output will be saved.

Parameters:

setup - The setup commands for the execed process.

cmd - The command and the arguments that should be run

stdoutFilename - The filename that stdout should be saved to

stderrFilename - The filename that stderr should be saved to

tailLength - The length of the tail to be saved.

useSetsid - Should setsid be used in the command or not.

Returns:

the modified command that should be run

Throws:

IOException

addCommand

public static String addCommand(List<String> cmd,
                boolean isExecutable)
                         throws IOException

Add quotes to each of the command strings and return as a single string

Parameters:

cmd - The command to be quoted

isExecutable - makes shell path if the first argument is executable

Returns:

returns The quoted string.

Throws:

IOException

captureDebugOut

public static List<String> captureDebugOut(List<String> cmd,
                           File debugoutFilename)
                                    throws IOException

Wrap a command in a shell to capture debug script's stdout and stderr to debugout.

Parameters:

cmd - The command and the arguments that should be run

debugoutFilename - The filename that stdout and stderr should be saved to.

Returns:

the modified command that should be run

Throws:

IOException

getUserLogDir

public static File getUserLogDir()

getJobDir

public static File getJobDir(String jobid)

Get the user log directory for the job jobid.

Parameters:

jobid - string representation of the jobid

Returns:

user log directory for the job

getJobDir

public static File getJobDir(JobID jobid)

Get the user log directory for the job jobid.

Parameters:

jobid - the jobid object

Returns:

user log directory for the job