Supported platforms

[David Holmes]

Hi Aleksei,

This is all news to me. Good news, but unexpected. As far as I was aware 
the 32-bit ARM port was dying a slow death and would eventually get 
removed. 64-bit ARM is of course very much alive and well under the 
Aarch64 porters - though I'm unclear if you are using that code for 
ARMv8 or the Oracle contributed code that used to be closed?

I'm also unclear whether you are pushing changes back up to OpenJDK for 
these platforms, or maintaining them locally? I haven't noticed anything 
(other than build tweaks) and am curious about the release of a Minimal 
VM for JDK 10 given the Minimal VM effectively died along with the 
stand-alone Client VM.

For JDK11 you will need to do some work for Condy (if not already done) 
as well as JFR and Nest-based Access Control (which you can see in the 
nestmates branch of the Valhalla repo), as you mention below. Not sure 
what else may be needed. There's been a lot of code refactoring and 
include file changes that have impact on platform specific code as well.

Cheers,
David

On 10/04/2018 5:23 PM, Aleksei Voitylov wrote:
> Hi David,
> 
> Speaking about the arm/ port, BellSoft has been releasing JCK-verified 
> binaries (as provided under the OpenJDK license) from the arm/ port for 
> the Raspberry Pi for JDK 9 [1] for a while and recently released one for 
> JDK 10 [2], including OpenJFX and Minimal VM support. On Raspberry Pi 2 
> (ARMv7) and Raspberry Pi 3 (ARMv8 chip running Raspbian) the binaries 
> produced from this port are passing all the required testing, including 
> the new features recently open-sourced by Oracle (such as AppCDS). As 
> far as JDK 11 is concerned, we are keeping track of the changes, 
> recently fixed a couple of build issues that slipped in [3, 4], are 
> working on Minimal Value Types support and, from what I can tell, will 
> need to look into JFR and Nest-Based Access Control. Please let us know 
> if we missed anything and we need to prepare for some other new features 
> for porting.
> 
> The intent is to keep the arm/ port in good shape and provide 
> well-tested binaries for the Raspberry Pi.
> 
> I believed Oracle was aware about BellSoft producing binaries from this 
> port [5], [6]. Based on twitter, it seems like at least some engineers 
> at Redhat and SAP are aware about it. Let me know if there is anything 
> else we need to do to spread the word about it with Oracle engineering. 
> For now, Boris (cced) is the engineer at BellSoft working on supporting 
> the arm/ port for the Raspberry Pi. Other than that, I really wonder 
> what "stepping up to take ownership of a port" means when it's upstream, 
> and there is some procedure we need to follow.
> 
> Thanks,
> 
> -Aleksei
> 
> [1] https://bell-sw.com/java-for-raspberry-pi-9.0.4.html
> [2] https://bell-sw.com/java-for-raspberry-pi.html
> [3] https://bugs.openjdk.java.net/browse/JDK-8200628
> [4] https://bugs.openjdk.java.net/browse/JDK-8198949
> [5] https://twitter.com/java/status/981239157874941955
> [6] https://twitter.com/DonaldOJDK/status/981874485979746304
> 
> 
>> We are in a situation where previously "supported" platforms (by Oracle)
>> are no longer supported as, AFAIK, no one has stepped up to take
>> ownership of said platforms - which is a requirement for getting a new
>> port accepted into mainline. Without such ownership the code may not
>> only bit-rot, it may in time be stripped out completely. Any interested
>> parties would then need to look at (re)forming a port project for that
>> platform to keep it going in OpenJDK (or of course they are free to take
>> it elsewhere).
>>
>> Cheers,
>> David
>>
> 
> On 09/04/2018 18:35, White, Derek wrote:
>> Hi Magnus,
>>
>>> -----Original Message-----
>>> Date: Mon, 9 Apr 2018 09:55:09 +0200
>>> From: Magnus Ihse Bursie<magnus.ihse.bursie at oracle.com>
>>> To: Simon Nash<simon at cjnash.com>,bren at juanantonio.info
>>> Cc:build-dev at openjdk.java.net, hotspot-dev developers
>>> 	<hotspot-dev at openjdk.java.net>
>>> Subject: Re: Supported platforms
>>> Message-ID:<4b1f262d-b9d2-6844-e453-dd53b42b2d74 at oracle.com>
>>> Content-Type: text/plain; charset=utf-8; format=flowed
>>>
>>> Simon,
>>>
>>> On 2018-04-08 16:30, Simon Nash wrote:
>>>> On 05/04/2018 02:26,bren at juanantonio.info  wrote:
>>>>> Many thanks with the link about the Platforms supported:
>>>>>
>>> http://www.oracle.com/technetwork/java/javase/documentation/jdk10cert
>>>>> config-4417031.html
>>>>>
>>>> This appears to be a list of the platforms that are supported
>>>> (certified) by
>>>> Oracle.? Where can I find the list of platforms that are supported by
>>>> OpenJDK?? For example, what about the following platforms that don't
>>>> appear on the Oracle list:
>>>>
>>>> Windows x86
>>>> Linux x86
>>>> aarch32 (ARMv7 32-bit)
>>>> aarch64 (ARMv8 64-bit)
>>>>
>>>> Are all these supported for OpenJDK 9, 10 and 11?
>>> There is actually no such thing as a "supported OpenJDK platform". While I
>>> hope things may change in the future, OpenJDK as an organization does not
>>> publicize any list of "supported" platforms. Oracle publishes a list of
>>> platforms they support, and I presume that Red Hat and SAP and others do
>>> the same, but the OpenJDK project itself does not.
>>>
>>> With that said, platforms which were previously supported by Oracle (like
>>> the one's you mentioned) tend to still work more-or-less well, but they
>>> receive no or little testing, and is prone to bit rot.
>>>
>>> /Magnus
>> Surely you meant to say "receive no or little testing BY ORACLE, and ORACLE IS NOT RESPONSIBLE FOR ANY bit rot."
>>
>> I haven't found a definitive list of supported OpenJDK platforms, but have an ad-hoc list of publicly available binaries:
>> - Major linux distros are supporting x64 and aarch64 (arm64), and probably other platforms.
>> - AdoptOpenJDK provides tested builds for most 64-bit platforms (x64, aarch64, ppc64, s390).
>>       -https://adoptopenjdk.net/releases.html
>> - Bellsoft provides support for 32-bit ARMv7.
>>      -https://bell-sw.com/products.html
>> - Azul provides 32-bit x86 and ARMv7 binaries as well as 64-bit x86 and aarch64.
>>      -https://www.azul.com/downloads/zulu/
>>
>> I'm sure there are several others I've missed - sorry!
>>   - Derek
>