JEP 175: Integrate PowerPC/AIX Port into JDK 8

[Christian Thalinger]

On Feb 4, 2013, at 12:42 AM, David Holmes <david.holmes at oracle.com> wrote:

> Hi Mark,
> 
> On 4/02/2013 6:22 PM, mark.reinhold at oracle.com wrote:
>> 2013/2/2 13:42 +0100, david.holmes at oracle.com:
>>> ...
>>> 
>>> I think the "risks" are a little under-stated. You have changed shared code and
>>> that potentially impacts all platforms (unless you have only added new
>>> functions unused on existing platforms?). There is also the matter of the
>>> "elephant in the room" - the existing proprietary PPC port that Oracle has for
>>> Java SE Embedded. Someone (from Oracle of course) will have to see how the
>>> proposed structure of the new port will impact the existing closed port. It
>>> might be a non-issue, or  a major issue - most likely somewhere in between.
>> 
>> Either way, issues with a proprietary port that's downstream of OpenJDK
>> are for the maintainers of that port to solve, regardless of whether the
>> maintainers work for Oracle.  The existence of a proprietary port cannot
>> hold back the contribution of an open port.
> 
> Ok.
> 
>> 
>>> I am also hoping that this will not simply be a copy'n'modify port as we have
>>> seen in the past. The proliferation of platform ifdefs in shared code is truly
>>> horrendous; as is the duplication across the purportedly platform-specific
>>> code. This problem wasn't addressed for the Mac port but in my opinion (and
>>> that is all it is) it needs to be before the community accepts any further
>>> ports.
>> 
>> I think it'd be a fine thing for that code to be refactored and cleaned
>> up, but I don't see that as a prerequisite for a new port coming in.
> 
> The code base will be unmanageable if we keep doing this copy'n'modify approach to porting, and the more ports we add the more impractical it becomes to try and retrofit a cleaner porting architecture. The OSX/bsd port is still causing us "indigestion".
> 
>>> I'd also like to understand the proposed maintenance model going forward. We
>>> (in Oracle) already have to accommodate our closed ports when they are affected
>>> by changes to common code that requires per-platform changes as well. Who will
>>> be providing the changes needed for aix-ppc? And how will that happen?
>> 
>> Every port needs a documented set of maintainers, and it's up to the
>> maintainers to track changes in shared code.  If a port stops being
>> maintained and rots for a significant period of time then it's likely to
>> be removed.  This is how similar long-lived projects (e.g., GCC) work.
> 
> Even if there are designated maintainers there is still a matter of how things will proceed. If someone is changing shared code who has the responsibility for making sure every port is accounted for? Do we have to coordinate things so that no changes are made until all changes are ready? Or do we allow things to break until the designated maintainers catch up?

It would be desirable to have an integration build and testing system that includes all platforms which are supported by OpenJDK.  Ideally this would be an open system where OpenJDK members (other companies than Oracle) could add their machines for the platforms they care about.

-- Chris

> 
>> Now that a port that's to be maintained by non-Oracle developers is being
>> proposed, I will soon propose a formal policy along these lines.
> 
> That would be good to see.
> 
> Thanks,
> David
> 
>> - Mark