Merging jdk/hs with jdk/jdk

jesper.wilhelmsson at jesper.wilhelmsson at
Wed Mar 14 21:00:28 UTC 2018


Over the last couple of years we have left behind a graph of
integration forests where each component in the JVM had its own
line of development. Today all HotSpot development is done in the
same repository, jdk/hs [1]. As a result of merging we have seen
several positive effects, ranging from less confusion around
where and how to do things, and reduced time for fixes to
propagate, to significantly better cooperation between the
components, and improved quality of the product. We would like to
improve further and therefore we suggest to merge jdk/hs into
jdk/jdk [2].

As before, we expect this change to build a stronger team spirit
between the merged areas, and contribute to less confusion -
especially around ramp down phases and similar. We also expect
further improvements in quality as changes that cause problems in
a different area are found faster and can be dealt with

In the same way as we did in the past, we suggest to try this out
as an experiment for at least two weeks (giving us some time to
adapt in case of issues). Monitoring and evaluation of the new
structure will take place continuously, with an option to revert
back if things do not work out. The experiment would keep going
for at least a few months, after which we will evaluate it and
depending on the results consider making it the new standard. If
so, the jdk/hs forest will eventually be retired. As part of this
merge we can also retire the newly setup submit-hs [3] repository
and do all testing using the submit repo based on jdk/jdk [4].

Much like what we have done in the past we would leave the jdk/hs
forest around until we see if the experiment works out. We would
also lock it down so that no accidental pushes are made to
it. Once the jdk/hs forest is locked down, any work in flight
based on it would have to be rebased on jdk/jdk.

We tried this approach during the last few months of JDK 10
development and it worked out fine there.

Please let us know if you have any feedback or questions!


[1] <>
[2] <>
[3] <>
[4] <>

More information about the jdk-dev mailing list