Re: Proposal for back-porting JFR to OpenJDK8u

[guangyu.zhu]

Hi Andrew, 
I still don't understand why feature backport is the right approach. What's the difference between feature backport and JEP? Can you give more comments?
Guangyu
------------------------------------------------------------------
Sender:Andrew Haley <aph at redhat.com>
Sent at:2018 Dec 6 (Thu) 17:38
To:Mario Torre <neugens at redhat.com>; guangyu.zhu <guangyu.zhu at aliyun.com>
Cc:jdk8u-dev <jdk8u-dev at openjdk.java.net>; kingsum.chow <kingsum.chow at gmail.com>
Subject:Re: Proposal for back-porting JFR to OpenJDK8u

Hi,

On 12/5/18 12:56 PM, Mario Torre wrote:
> On Wed, Dec 5, 2018 at 10:56 AM guangyu.zhu <guangyu.zhu at aliyun.com> wrote:
>>
>> Java Flight Recorder (JFR) has been open-sourced in OpenJDK 11 for some time. The tool is very useful for trouble-shooting and performance tuning. However, a lot of Java applications are still running on JDK 8. Thus we back-ported JFR from 11 to 8 on x86-64 platform, which actually has been widely used at Alibaba. We believe it is stable enough to be contributed back to the community.  By contributing our patch, the community can help make it work on other platforms too. So, I’d like to file a JEP and propose contributing it to OpenJDK8project, then people can work together to make the patch be pushed finally. What do you think?
>>
>> Thanks,
>> Guangyu (Greg) Zhu
> 
> This is awesome, I've been toying with this idea myself lately, so I'm
> very happy you would like to contribute this code, I would support
> this proposal completely, and I'm very curious to see the actual
> patch.
> 
> I think you are right in filing a JEP, it's the right approach for such changes.

I'm not convinced that JEPs are appropriate for backports to jdk8u. We
should instead evaluate this as a feature backport.

We cannot change any APIs in the core Java namespaces. This is a legal
requirement.

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
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