If you are responsible for a GlassFish module container, please read on.
The deployment framework makes available the DeploymentContext to all
deployers that need to work with a given application. The intent has
always been that the scope of a DeploymentContext is limited to
deployment (or undeployment) processing only, not to the running
application container.
As part of our work to improve the memory footprint, beginning very
soon (later today or within a day or so) the deployment framework will
clear out the DeploymentContext's transient application metadata
(accessible using the DeploymentContext.getTransientAppMetadata
methods) at the end of deployment. No code should have been relying
on this data past that point anyway.
So far testing has not revealed any problems caused by clearing out
that data, but you should double-check that your module will not be
affected.
We are adding this clean-up step because there are lingering
references - after deployment - to the DeploymentContext which keeps
it reachable after it should be eligible for GC. The DC's references
to the transient app metadata consumed quite a bit of memory.
Eventually we plan to make sure there are no such lingering references
to the DC itself, in which case the DC and all referenced objects can
be GCed. But that might be too risky for 3.1.1, so as a first step we
are clearing out the transient app metadata.
In the future you might need to change any container code that relies
on a saved reference to the DC in order to improve further the memory
footprint. We might not make this change right away, but please be
aware that this could be very likely for some release past 3.1.1 if
not for 3.1.1 itself, depending on the work we are continuing to do on
improving the memory footprint.
Please let me know if you have any questions.
- Tim