[aarch64-port-dev ] RFR: Bulk integration of Shenandoah 2018-05-15

[Andrew Haley]

On 06/13/2018 07:38 PM, Andrew Hughes wrote:
> On 13 June 2018 at 16:09, Andrew Haley <aph at redhat.com> wrote:
>> On 06/13/2018 04:02 PM, Andrew Hughes wrote:
>>
>>> Clearly though, you want them for Shenandoah earlier than that. In
>>> this case, add them to aarch64/jdk8u and then merge that into the
>>> Shenandoah tree, rather than applying directly to Shenandoah. That
>>> way, all three trees (the two aarch64 project ones and the
>>> Shenandoah project one) have these fixes.
>>
>> Mmm, but that's when *I* start to get nervous about the divergence
>> between what we ship as JDK 8 to everyone and OpenJDK 8 upstream.  Of
>> course there's and inevitable tension, but we must be very careful not
>> to break any production systems.
> 
> Indeed, which is why I want them to have more scrutiny by going into
> aarch64/jdk8u
> on their own, rather than being part of a huge Shenandoah merge which only goes
> into aarch64/jdk8u-shenandoah. I completely missed them in the Shenandoah merge
> until they conflicted with us applying one of them already in our RPMs.

I see.  OK, so we need to split such commits very carefully.

> I also wouldn't suggest including patches that aren't already in OpenJDK 8
> upstream. What we're talking about is fast-tracking patches that are of
> high priority to us, rather than deviating from OpenJDK 8 long term.

Right.  Or, I guess upstream patches which are Shenandoah dependencies.

> The way we build our RPMs is that we use the
> aarch64/shenandoah-jdk8u HotSpot on aarch64 & x86_64 and
> aarch64/jdk8u on all other architectures.

Why do we still do that?  Should we review that policy?  The only
other architectures are, what, PPC and S/390?

> If patches are only included in the former, we introduce the risk of
> seeing breakage on some architectures, but not others, which can
> create further confusion.

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