New candidate JEP: 362: Deprecate the Solaris and SPARC Ports

[Florian Weimer]

* John Paul Adrian Glaubitz:

> On 11/4/19 12:34 PM, Andrew Haley wrote:
>>> I feel like that OpenJDK is starting to develop into a direction of
>>> low portability again. When I started working on OpenJDK, I had
>>> hoped to be able to help make OpenJDK and Java more portable. But I
>>> feel there is no real interest in the OpenJDK community to make Java
>>> available on a wide variety of platforms besides x86, ARM, POWER and
>>> S390x.
>> 
>> Right. It's not about whether people are interested in the port but
>> whether they are prepared to invest in it. From the AArch64 port point
>> of view, I know just how much investment that is.
>
> I already mentioned this in a private reply to someone else: I think
> one of the problems with OpenJDK in this regard is that the core developers
> are testing their changes on the platforms supported by Oracle only.
>
> I very often see mails with the subject "RFR-NNNNNN: Build broken on $ARCH
> after JDK-XXXXXXX" which is something I don't see that often in other
> projects like Rust or GCC. Sure, they also have regressions that affect
> certain architectures only, but in OpenJDK this happens much more frequently
> from what I have observed.

It happens regularly with glibc (mostly with Hurd and s390x) and GCC
(AIX boostrap failures anyone?).  It is simply the result of a tiered
building and testing strategy.

I don't know what the numbers look like for OpenJDK, but building
glibc on all targets costs between $10 and $20 in the public cloud.
That's just *building*, no code execution tests have actually run at
that point.  That means that commits have to be tested in batches,
usually after they land in the main development repository.

> In my opinion, it would be more efficient if everyone tested their
> changes on all supported architectures. This way potential
> regressions are detected much earlier and will most likely not reach
> get committed to the main repository.

Sure, but that means that if you want to keep the SPARC port alive,
*you* will have to provide porter boxes, builders and testers.

> The community has set up a variety of machines in the GCC compile farm to make
> this possible:
>
>> https://gcc.gnu.org/wiki/CompileFarm
>
> Any open source developer can request an account there and test their changes
> on various different platforms.

Aren't all SPARC compile farm machines offline?

> That's not the experience I made. Usually GCC developers make their
> changes across all architectures and test them. It's not that code
> for m68k is touched by the m68k maintainer only, for example.
>
> GCC is rather successful with their model, in my opinion, which can
> be seen from the large number of supported targets which even includes
> very obscure and old ones like PDP-11 and VAX.

GCC faces pretty much the same issues as OpenJDK.  As you well know,
the m68k target (and a couple of others) will likely be removed along
with the removal of the cc0 support due to its maintenance cost, same
rationale as with OpenJDK.