org.apache.hadoop.yarn.util

Class Log4jWarningErrorMetricsAppender

java.lang.Object

org.apache.log4j.AppenderSkeleton

org.apache.hadoop.yarn.util.Log4jWarningErrorMetricsAppender

All Implemented Interfaces:

org.apache.log4j.Appender, org.apache.log4j.spi.OptionHandler

@InterfaceAudience.Private
 @InterfaceStability.Unstable
public class Log4jWarningErrorMetricsAppender
extends org.apache.log4j.AppenderSkeleton

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Log4jWarningErrorMetricsAppender.Element

Field Summary

Fields

Modifier and Type	Field and Description
static String	LOG_METRICS_APPENDER

Fields inherited from class org.apache.log4j.AppenderSkeleton

closed, errorHandler, headFilter, layout, name, tailFilter, threshold

Constructor Summary

Constructors

Constructor and Description
Log4jWarningErrorMetricsAppender() Create an appender to keep track of the errors and warnings logged by the system.
Log4jWarningErrorMetricsAppender(int cleanupIntervalSeconds, long messageAgeLimitSeconds, int maxUniqueMessages) Create an appender to keep track of the errors and warnings logged by the system.

Method Summary

Modifier and Type	Method and Description
protected void	append(org.apache.log4j.spi.LoggingEvent event)
void	close()
static Log4jWarningErrorMetricsAppender	findAppender()
long	getCleanupInterval()
List<Integer>	getErrorCounts(List<Long> cutoffs) Get the counts of errors in the time periods provided.
List<Map<String,Log4jWarningErrorMetricsAppender.Element>>	getErrorMessagesAndCounts(List<Long> cutoffs) Get the errors and the number of occurrences for each of the errors for the time cutoffs provided.
int	getMaxUniqueMessages()
long	getMessageAgeLimitSeconds()
List<Integer>	getWarningCounts(List<Long> cutoffs) Get the counts of warnings in the time periods provided.
List<Map<String,Log4jWarningErrorMetricsAppender.Element>>	getWarningMessagesAndCounts(List<Long> cutoffs) Get the warning and the number of occurrences for each of the warnings for the time cutoffs provided.
boolean	requiresLayout()
void	setCleanupInterval(long cleanupInterval)
void	setMaxUniqueMessages(int maxUniqueMessages)
void	setMessageAgeLimitSeconds(long messageAgeLimitSeconds)

Methods inherited from class org.apache.log4j.AppenderSkeleton

activateOptions, addFilter, clearFilters, doAppend, finalize, getErrorHandler, getFilter, getFirstFilter, getLayout, getName, getThreshold, isAsSevereAsThreshold, setErrorHandler, setLayout, setName, setThreshold

Methods inherited from class java.lang.Object

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

Field Detail

LOG_METRICS_APPENDER

public static final String LOG_METRICS_APPENDER

See Also:

Constant Field Values

Constructor Detail

Log4jWarningErrorMetricsAppender

public Log4jWarningErrorMetricsAppender()

Create an appender to keep track of the errors and warnings logged by the system. It will keep purge messages older than 2 days. It will store upto the last 500 unique errors and the last 500 unique warnings. The thread to purge message will run every 5 minutes, unless the 500 message limit is hit earlier.

Log4jWarningErrorMetricsAppender

public Log4jWarningErrorMetricsAppender(int cleanupIntervalSeconds,
                                        long messageAgeLimitSeconds,
                                        int maxUniqueMessages)

Create an appender to keep track of the errors and warnings logged by the system.

Parameters:

cleanupIntervalSeconds - the interval at which old messages are purged to prevent the message stores from growing unbounded

messageAgeLimitSeconds - the maximum age of a message in seconds before it is purged from the store

maxUniqueMessages - the maximum number of unique messages of each type we keep before we start purging

Method Detail

append

protected void append(org.apache.log4j.spi.LoggingEvent event)

Specified by:

append in class org.apache.log4j.AppenderSkeleton

close

public void close()

requiresLayout

public boolean requiresLayout()

getErrorCounts

public List<Integer> getErrorCounts(List<Long> cutoffs)

Get the counts of errors in the time periods provided. Note that the counts provided by this function may differ from the ones provided by getErrorMessagesAndCounts since the message store is purged at regular intervals to prevent it from growing without bounds, while the store for the counts is purged less frequently.

Parameters:

cutoffs - list of timestamp cutoffs(in seconds) for which the counts are desired

Returns:

list of error counts in the time periods corresponding to cutoffs

getWarningCounts

public List<Integer> getWarningCounts(List<Long> cutoffs)

Get the counts of warnings in the time periods provided. Note that the counts provided by this function may differ from the ones provided by getWarningMessagesAndCounts since the message store is purged at regular intervals to prevent it from growing without bounds, while the store for the counts is purged less frequently.

Parameters:

cutoffs - list of timestamp cutoffs(in seconds) for which the counts are desired

Returns:

list of warning counts in the time periods corresponding to cutoffs

getErrorMessagesAndCounts

public List<Map<String,Log4jWarningErrorMetricsAppender.Element>> getErrorMessagesAndCounts(List<Long> cutoffs)

Get the errors and the number of occurrences for each of the errors for the time cutoffs provided. Note that the counts provided by this function may differ from the ones provided by getErrorCounts since the message store is purged at regular intervals to prevent it from growing without bounds, while the store for the counts is purged less frequently.

Parameters:

cutoffs - list of timestamp cutoffs(in seconds) for which the counts are desired

Returns:

list of maps corresponding for each cutoff provided; each map contains the error and the number of times the error occurred in the time period

getWarningMessagesAndCounts

public List<Map<String,Log4jWarningErrorMetricsAppender.Element>> getWarningMessagesAndCounts(List<Long> cutoffs)

Get the warning and the number of occurrences for each of the warnings for the time cutoffs provided. Note that the counts provided by this function may differ from the ones provided by getWarningCounts since the message store is purged at regular intervals to prevent it from growing without bounds, while the store for the counts is purged less frequently.

Parameters:

cutoffs - list of timestamp cutoffs(in seconds) for which the counts are desired

Returns:

list of maps corresponding for each cutoff provided; each map contains the warning and the number of times the error occurred in the time period

getCleanupInterval

public long getCleanupInterval()

setCleanupInterval

public void setCleanupInterval(long cleanupInterval)

getMessageAgeLimitSeconds

public long getMessageAgeLimitSeconds()

setMessageAgeLimitSeconds

public void setMessageAgeLimitSeconds(long messageAgeLimitSeconds)

getMaxUniqueMessages

public int getMaxUniqueMessages()

setMaxUniqueMessages

public void setMaxUniqueMessages(int maxUniqueMessages)

findAppender

public static Log4jWarningErrorMetricsAppender findAppender()