proposal - dissolve the OpenJDK hsx Project after jdk8 ships
staffan.larsen at oracle.com
Tue Dec 10 23:21:26 PST 2013
On 10 dec 2013, at 22:02, John Coomes <John.Coomes at oracle.com> wrote:
> The hsx Project was created to make hotspot development independent of
> specific JDK releases, so the same source could then delivered into
> multiple JDK releases simultaneously. This has worked pretty well for
> a number of years, allowing us to get significant features and
> performance improvements into shipping, supported JDK releases much
> more quickly.
> However, it has also complicated hotspot development in several ways.
> We have to maintain compatibility with multiple JDK
> releases--supporting old operating systems, old tool chains and old
> JDK APIs. It is also more difficult to make large-scale or behavioral
> changes, since delivering into update releases requires a high degree
> of compatibility and allows only a relatively short time for
> stabilization. And there is also the overhead of a separate OpenJDK
> Project, separate version tracking in the bug database and the mental
> overhead of having to map a hotspot version to/from a jdk version.
> Further, because of compatibility concerns, we have not delivered the
> same source into multiple JDK releases for more than 18 months,
> incurring the costs without reaping the benefits. So I propose that
> the hsx Project be dissolved after jdk8 has shipped, and that hotspot
> development move to be more closely aligned with future JDK releases.
> In practical terms this means that:
> - the general process for delivering hotspot into jdk8 will
> not change, to avoid disruption late in the release cycle.
> The remaining critical fixes needed for jdk8 will continue to
> be made in the existing hsx repos.
> - as the number of expected jdk8 fixes decreases to a trickle,
> jdk8 development and testing should move from the hsx group
> repos (e.g., hotspot-gc, hotspot-rt, etc.) to a single
> stabilization repo (possibly hsx/hotspot-main). Alejandro
> Murillo, the hotspot gatekeeper, will coordinate this.
> - hsx Project Author/Committer/Reviewer status will be
> transferred to the new jdk9   and jdk8u  
> - the bulk of hotspot development will take place in new repos
> that are part of the jdk9 project (e.g.,
> http://hg.openjdk.java.net/jdk9/hotspot-comp, etc.)
> - bug fixes appropriate for jdk8 update releases will have to
> be selected and backported individually. I anticipate that a
> new jdk8 update tree for hotspot will be created (name tbd),
> so that we can continue to do pre-integration testing and bulk
> integrations as we have done for jdk7 updates.
> - hotspot bugs for jdk9 and jdk8 updates will be tracked in
> JBS using the jdk version number, not a separate hotspot
> version number (e.g., we'll use '9' or '8u20' instead of
> 'hs26' or 'hs25.20').
> - after the last hotspot bug fix has been delivered to jdk8,
> the hsx Project repos will become read-only and maintained
> simply for archival purposes.
> Apologies for the length of this messages; I'm hoping to answer the
> obvious questions in advance. Please follow up if you have comments
> or if there are any I missed.
>  http://mail.openjdk.java.net/pipermail/announce/2013-October/000155.html
>  http://mail.openjdk.java.net/pipermail/announce/2013-November/000156.html
>  http://mail.openjdk.java.net/pipermail/announce/2013-December/000157.html
>  http://mail.openjdk.java.net/pipermail/discuss/2013-December/thread.html
More information about the hotspot-dev