Zhanghao Chen created FLINK-37735:
-------------------------------------

             Summary: Replace class.newInstance with constructor.newInstance
                 Key: FLINK-37735
                 URL: https://issues.apache.org/jira/browse/FLINK-37735
             Project: Flink
          Issue Type: Sub-task
          Components: API / Type Serialization System
            Reporter: Zhanghao Chen
         Attachments: image-2025-04-27-13-05-28-554.png, 
image-2025-04-27-13-14-18-941.png

*Problem*

Flink's PojoSerializer and TupleSerializer uses {{class.newInstance}} to 
instiantiate a new instance. The {{class.newInstance}} call will get caller 
class and do access check on each invocation, which consumes much CPU, as 
depicted in the flame graph below. It is also marked @Deprecated since JDK9, 
and is subject to removal in later JDK versions.

!image-2025-04-27-13-05-28-554.png|width=730,height=137!

*Proposal*

The suggested alternative is to use {{{}constructor.newInstance{}}}, which 
allows bypassing the access check completely after setting accessible to true. 
It also throws more specific exception on invocation error.

The performance gets boosted by ~5% on the Flink POJO benchmark (tested on my 
laptop with JDK17.0.14):
​ !image-2025-04-27-13-14-18-941.png!



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

Reply via email to