Garbage Collection

Garbage Collector for Embedded Devices

Implement a garbage collector that has beneficial characteristics for embedded devices. For example, the collector could avoid compaction in certain scenarios.

Interested mentors:

Garbage Collection Visualization

the Jikes RVM has had GC visualization previously through the GCspy framework. This has become slightly out-of-date and it would be interesting to improve it and possibly look to integrate the visualization side of the work with a sister project of the RVM's tuning fork. 

http://jira.codehaus.org/browse/RVM-388 

Interested mentors: Richard Jones

New Garbage Collection Implementations for MMTk

We would be interested in hearing about adding new GC implementations to MMTk. As such the complexity of such a thing is high, we will take particular care when looking at your experience with relation to an application for this project.

Interested mentors:

Compilers

Copy eliminating baseline compiler

A new framework for baseline code generation using a copy eliminating baseline compiler.

Interested mentors: Eliot Moss, Ian Rogers

x86 64 compiler support

Related to the previous project, continue efforts to port to x86 64 the Jikes RVM.

Interested mentors: Ian Rogers

strictfp support

http://jira.codehaus.org/browse/RVM-235

Interested mentors: Ian Rogers

Reduce cost of inlining runtime services

http://jira.codehaus.org/browse/RVM-148

Interested mentors: Ian Rogers

Loop unrolling

Implement a better loop unrolling phase taking into account various considerations about when and how to unroll.

Interested mentors: Ian Rogers

Java Operating Systems

Work on the continued integration of the RVM with JNODE

http://jira.codehaus.org/browse/RVM-382

Interested mentors: Ian Rogers

Runtime services

Class Unloading

Currently all classes share a "Java table-of-contents" or the JTOC which has no support for unloading classes. We need to restructure the JTOC interface to support class unloading by making it per class loader, or per class. This is likely to also involve looking into modifying the current calling conventions.

http://jira.codehaus.org/browse/RVM-324

Interested mentors: Robin Garner, Ian Rogers

Lock Reservation/Biasing

Interested mentors: Tony Hosking, Ian Rogers

Native Threading

Interested mentors: Tony Hosking, Ian Rogers

Harmony class library support

http://jira.codehaus.org/browse/RVM-358

Interested mentors: Ian Rogers, Tim Ellison

OpenJDK class library support

The OpenJDK class libraries are the standard class libraries in use in Sun and other production VMs. They are now available under the GPL but with a native interface implemented typically in a file called jvm.cpp (see Cacao). We would like to integrate with OpenJDK and fix likely issues in wanting to have Java-in-Java implementations of a lot of their calls, as well as support for different threading models.

Interested mentors: Andrew Hughes

Modularity

Currently there is a connection between different parts of the RVM that is less than desirable. For example, the on-stack-replacement algorithm is implemented in parts in the class loader. We would like to have better isolation of components to more easily allow plug in replacements to be created. Such changes are likely to have an effect across the code base, so interacting with the development community will be important.

Interested mentors: Ian Rogers