[HADOOP-11223] Offer a read-only conf alternative to new Configuration()

• Type: Bug
• Status: Patch Available
• Priority: Major
• Resolution: Unresolved
• Component/s: conf
• Labels: Performance
• Target Version/s: 2.8.3
• Assignee: Michael Miller
• Reporter: Gopal Vijayaraghavan
• Created: 24/Oct/14 04:21
• Updated: 04/Sep/19 22:05

Description

new Configuration() is called from several static blocks across Hadoop.

This is incredibly inefficient, since each one of those involves primarily XML parsing at a point where the JIT won't be triggered & interpreter mode is essentially forced on the JVM.

The alternate solution would be to offer a Configuration::getDefault() alternative which disallows any modifications.

At the very least, such a method would need to be called from

1. org.apache.hadoop.io.nativeio.NativeIO::<clinit>()
2. org.apache.hadoop.security.SecurityUtil::<clinit>()
3. org.apache.hadoop.yarn.factory.providers.RecordFactoryProvider::<clinit>

Issue Links

• links to: GitHub Pull Request #473