Packed Objects

[Daniel Hicks]

Just as an aside, the "Classic" JVM on IBM iSeries was doing a primitive 
form of packed objects (only for system objects) years ago.  For classes 
in the system classpath there was an attribute that could specify the 
offsets of individual fields, allowing "native" data structures to be 
accessed directly from Java code.

On 11/24/2012 2:00 PM, hotspot-dev-request at openjdk.java.net wrote:
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>     1. PackedObjects (Doug Lea)
>     2. Re: [concurrency-interest] RFR (S): JEP-142: Reduce Cache
>        Contention	on Specified Fields (Aleksey Shipilev)
>     3. Re: RFR (S): JEP-142: Reduce Cache Contention on Specified
>        Fields (Aleksey Shipilev)
>     4. Re: RFR (S): JEP-142: Reduce Cache Contention on Specified
>        Fields (Michael Barker)
>     5. Re: RFR (S): JEP-142: Reduce Cache Contention on Specified
>        Fields (Aleksey Shipilev)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Fri, 23 Nov 2012 15:00:29 -0500
> From: Doug Lea <dl at cs.oswego.edu>
> Subject: PackedObjects
> To: hotspot-dev at openjdk.java.net
> Message-ID: <50AFD5DD.2000804 at cs.oswego.edu>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
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>
> On the occasion of subscribing to this list for the sake of
> exchanges about @Contended, I figure that it is also worth
> alerting folks who haven't heard about IBM's PackedObject
> proposal that they now have released some slides etc at
>
> http://www.slideshare.net/mmitran/ibm-java-packed-objects-mmit-20121120
>
> This is a VM-level approach to supporting value/struct/tuple
> types, that I hope catches on and turns into a JEP. Of all
> the ways to do this sort of thing, it strikes me as being
> among the few that might possibly succeed (and actually has
> succeeded at least to the point of a J9 implementation).
>
> -Doug
>
-- 
Dan Hicks
Experience is the name everyone gives for their mistakes.  --Oscar Wilde