ReflectionUtils performance regression
--------------------------------------

                 Key: HADOOP-6133
                 URL: https://issues.apache.org/jira/browse/HADOOP-6133
             Project: Hadoop Common
          Issue Type: Improvement
            Reporter: Todd Lipcon
            Assignee: Todd Lipcon
         Attachments: Test.java

HADOOP-4187 introduced extra calls to Class.forName in ReflectionUtils.setConf. 
This caused a fairly large performance regression. Attached is a microbenchmark 
that shows the following timings (ms) for 100M constructions of new instances:

Explicit construction (new Test): around ~1.6sec
Using Test.class.newInstance: around ~2.6sec
ReflectionUtils on 0.18.3: ~8.0sec
ReflectionUtils on 0.20.0: ~200sec

This illustrates the ~80x slowdown caused by HADOOP-4187.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.

Reply via email to