[MAPREDUCE-2372] TaskLogAppender mechanism shouldn't be set in log4j.properties

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.22.0
• Fix Version/s: 0.22.0
• Component/s: task
• Hadoop Flags: Reviewed
• Assignee: Todd Lipcon
• Reporter: Todd Lipcon
• Created: 09/Mar/11 20:05
• Updated: 12/Dec/11 06:19
• Resolved: 19/May/11 20:16

Description

The TaskLogAppender log4j appender relies on using log4j.properties to pass in some Java system properties into properties of the logger. This is problematic since we've often found that users have customized log4j.properties and don't upgrade it when they upgrade the version of Hadoop.

Since this is really an internal mechanism of how the task runner passes task info to the TLA, we shouldn't rely on these settings in log4j.properties at all. Rather, we should just get the system properties directly from System.getProperty.

Issue Links

• is related to: HADOOP-7308 Remove unused TaskLogAppender configurations from log4j.properties