HotSpot 14

[Erik Trimble]

Andrew John Hughes wrote:
> 2009/5/15 Erik Trimble <Erik.Trimble at sun.com>:
>   
>> Andrew John Hughes wrote:
>>     
>>> Hi all (especially Joe),
>>>
>>> Now that the HotSpot Express repositories are available, what is the
>>> plan for including hs14 in OpenJDK6?
>>>
>>> I did a pull of the base changeset from HS express (0) into OpenJDK6's
>>> hotspot repo. yesterday as a test, and it seems to apply fairly well.
>>> The conflicts all seem to be whitespace changes (though there's a lot
>>> of them -- ~210 files are affected).
>>>
>>> Do we still plan to maintain a version of HotSpot in OpenJDK6 or will
>>> HS Express just be used directly?
>>>
>>> Thanks,
>>>
>>>       
>> Frankly, I think this is up to the Community.
>>
>> I'm still not 100% sure of the complete list of who has write access to the
>> OpenJDK6 stuff, but I /think/ the proper way to do this is not move any HSX
>> release into the main OpenJDK6 forest until there is  consensus that It's
>> Time.
>>
>>     
>
> The list is here: http://db.openjdk.java.net/people for your
> delectation and delight.
>
>   
Thanks!


>> Now, that said, maybe It's Time Right Now.
>>
>>     
>
> IcedTea (i.e. the version of OpenJDK6 people are actually using on
> their distros today) has already been shipping HotSpot 14 for some
> time.  So I think not only is the time right for OpenJDK6 upstream to
> also upgrade, but that it's perhaps long overdue.
>
>   
I'll check with Joe, but I think it's on my to-do list to push HSX14 to 
OpenJDK sometime before JavaOne. 

>> Given that the HSX repos are going to be almost exclusively Sun-only
>> writable (in practice, not necessarily by design), I think that the VM in
>> OpenJDK6 should be pulled from an HSX repo, and then have various
>> community-desired patches applied there, rather than try to work directly on
>> an HSX repo.  That is, I expect the various HSX repos to be a reflection of
>> what Sun is doing, and the VM in OpenJDK6 should be a reflection of what the
>> Community chooses to do with the HSX work from Sun.
>>
>>     
>
> My preference would be for patches to go into HotSpot Express and then
> OpenJDK6 just pull a stable version regularly.  I've already had
> patches committed to HotSpot as have others working on IcedTea, so I
> don't see an issue there.
>   

Well, this needs further discussion.  There's still some conflict here 
as to whether or not we're going to ship the Sun JDK 6 Update release 
train as a superset of the OpenJDK6 + HSX repositories, or if there will 
be things in those open repos that we exclude from the Sun JDK6 Updates.

If the first case is what is happening (i.e. Sun's JDK is a superset of 
OpenJDK6+HSX), then, yes, we (that is, the entire Community+Sun) should 
just patch the appropriate HSX repo, and periodically pull it over into 
the OpenJDK6 forest after stabilization.   If, on the other hand, the 
second case is what is To Be, then only certain community-submitted 
patches will be integrated into HSX, which means that the actual 
development of Hotspot for OpenJDK6 will have to happen in the OpenJDK6 
forest directly.  In essence, if we chose the 2nd case, there will need 
to be 3 VM repositories:   HSX for the stuff that's going to be the Sun 
JDK6 release, IceTea for the patches to the HSX repository that aren't 
going into Sun's JDK, and OpenJDK6, which is HSX+IceTea (stabilized).


-- 
Erik Trimble
Java System Support
Mailstop:  usca22-123
Phone:  x17195
Santa Clara, CA
Timezone: US/Pacific (GMT-0800)