Alibaba Open Source OpenJDK Long-Term Support Version Alibaba Dragonwell

At the Alibaba Cloud Summit in Beijing on March 21, Alibaba officially announced the open source OpenJDK long-term support version Alibaba Dragonwell. As the only Chinese representative of the Supreme Executive Committee of the Java Community Process (JCP), a global management organization for Java, and one of the few OpenJDK customizers in the Java ecosystem outside of Oracle, Alibaba Dragonwell's open source is Alibaba's priority to global Java developers. pound gift.


Beijing Alibaba Cloud Summit Announces Alibaba Dragonwell Open Source Site

This is Alibaba Dragonwell
Alibaba Dragonwell is a free OpenJDK distribution. It provides long-term support, including performance enhancements and security fixes. Alibaba Dragonwell currently supports the X86-64/Linux platform, which can greatly improve stability, efficiency, and performance when deploying large-scale Java applications in data centers. Alibaba Dragonwell is compatible with the Java SE standard, and users can use Alibaba Dragonwell to develop and run Java applications.


This time, the preview version of Alibaba Dragonwell 8 released by Alibaba corresponds to the version of OpenJDK 8. The open source of Alibaba Dragonwell provides a new choice for global Java developers. At the same time, for Alibaba Cloud, Alibaba Dragonwell will release the two versions of LTS, Java 8 and Java 11, with the Alibaba Cloud VM image, and provide them to Alibaba Cloud customers for free.

AJDK's superior successor - Alibaba Dragonwell
The predecessor of Alibaba Dragonwell was the AJDK (Alibaba/AlipayJDK) used internally by Alibaba. As early as 2010, Alibaba started the development of OpenJDK-based open source software, and started the optimization and customization of OpenJDK 8 in 2015.

As the cornerstone of Alibaba's Java applications, AJDK supports all Java businesses in Alibaba's economy. It has withstood multiple Double Eleven tests and accumulated practical experience in a large number of business scenarios. As an OpenJDK customizer in the Java ecosystem outside of Oracle, Ali has spared no effort to continue to open up new frontiers in Java:

In October 2015, AJDK8.0.0 was released to achieve multi-tenancy, support high-density deployment and resource isolation.
In May 2016, AJDK 8.1.1 was released, supporting JWarmup and supporting Java applications to be compiled in advance at runtime.
In October 2016, AJDK 8.2.4 was released, which implements Wisp coroutines and effectively improves the performance of Java applications by more than 30%.
In January 2018, AJDK 8.4.7 was released, based on the customized version of ZenGC (G1 based) for Alibaba's big data scenarios.
In February 2018, the AJDK-based Java Profiling tool Java Event Tracing (JET) was released.
As an open source version of AJDK, Alibaba Dragonwell follows AJDK's technical advantages and technical experience in practical scenarios. After open source, each release of Alibaba Dragonwell will synchronize with the latest update of OpenJDK 8 (OpenJDK 8u), and will add Alibaba's 'value-add' function based on Alibaba's engineering practice. The Alibaba Dragonwell version will pass the JCK compatibility suite test to ensure Java compatibility.

Alibaba Dragonwell and OpenJDK
Oracle announced that Java8 will stop updating after January 2019, and Java11 and later versions will no longer provide free long-term support (LTS) support. It is foreseeable that more and more Java developers will turn to OpenJDK in the future. Alibaba has long been committed to working closely with the OpenJDK community, the gathering place for Java technology advancement. Alibaba Dragonwell will keep pace with the community version and fully integrate Alibaba's business practices and technical experience to provide Java developers with a good solution. .

Advantages of Alibaba Dragonwell 8

Porting the Java Flight Recorder (JFR) function of the upstream Java 11, Java developers can collect detailed profiling information during the JVM running process through JFR, and cooperate with Java Mission Control (JMC) to greatly improve the efficiency of problem diagnosis and performance optimization of Java applications;
Integrating AJDK's JWarmup technology, JWarmup has been established as a Java Enhancment Proposal (JEP) in OpenJDK, and is expected to be added to the standard Java release in the future. In the data center, JWarmup can dynamically precompile Java code in combination with application traffic scheduling timing, which can effectively reduce CPU load and RT timeout caused by traditional Just-in-Time warmup.
Provides improvements in GC problem diagnosis Servicibility. For details, refer to Alibaba Dragonwell 8 User Guide
Alibaba Dragonwell Roadmap
As a downstream of OpenJDK, Alibaba Dragonwell will release new versions every quarter mainly including:

Community upstream security/critical bug fixes
Ali customized functions, bug fixes, etc.
Function porting of Java 8 and later versions based on Alibaba engineering practice
We plan to gradually open source the technological innovation accumulated by Alibaba using AJDK and contribute to the community. Meanwhile, we expect to release Alibaba Dragonewell 11 by the end of 2019.

Github Link: https://github.com/alibaba/dragonwell8

Alibaba Dragonwell FAQ
On the eve of the announcement of open source, InfoQ reporters interviewed Li Sanhong, senior technical expert of Alibaba Cloud Intelligent Basic Products Division, and Kingsum Chow (Zhou Jingsen), researcher of Alibaba Cloud Intelligent Basic Products Division.

Q1. What is the origin of the name Alibaba Dragonwell?

"Dragonwell" is translated as Longjing in Chinese, which symbolizes China's tea culture, and happens to be the characteristic of Hangzhou (where Alibaba's headquarters is located); the word "well" is usually described as a gathering of water sources for everyone to enjoy. We hope to bring together all the development The power of the creators continues to improve the project and ultimately contribute to all users.

Q2. Is the open source Alibaba Dragonwell the same thing as the AJDK used internally by Alibaba?

The open source Alibaba Dragonwell this time is still different from the AJDK used internally by Alibaba. Alibaba Dragonwell is the open source version of AJDK and the successor of AJDK technology. The current open source version does not contain all the features of AJDK, such as multi-tenancy, Wisp coroutines, ZenGC, etc. After that, we will consider gradually transitioning the functions of AJDK to Alibaba Dragonwell.

Q3. What is the relationship between Alibaba Dragonwell and OpenJDK? Will Alibaba continue to maintain the OpenJDK community?

Alibaba Dragonwell must be the downstream of OpenJDK. Each Alibaba Dragonwell release will synchronize with the latest upstream updates and be tested by Alibaba's internal large-scale application cluster. At the same time, Alibaba will also actively contribute the technology accumulation on AJDK to OpenJDK, and actively participate in the project update and maintenance of the community. We look forward to working closely with the OpenJDK community to advance the development of OpenJDK.

Q4. How do you view the upgrade of the Java version? How do you view the relationship between Oracle JDK and OpenJDK?

Java 8 is by far the most widely used version, and its community is very sticky. In Java circles, you will find a very interesting phenomenon: no matter how tempting the updates given by the new version, most Java developers seem not interested and still stick to their choices. Indeed, Java 8 was such a successful release that many developers didn't see the need to update to other versions, which may have something to do with long-established habits and inherent trust. With the development of Java over the years, most developers have become accustomed to trusting the official Oracle JDK and have not paid enough attention to the community OpenJDK version. Therefore, switching from Oracle JDK to OpenJDK requires a process. However, with the efforts of these international technology companies, the ecosystem of OpenJDK will become more and more complete, and its functions will be more complete. Facing continuous security updates and the in-depth participation of many large companies, this project should become a part of the Java ecosystem. important public resource.

Author: Ali Open Source