rtjavareq

Requirements For Real-time Extensions

For the Java™ Platform

Published on October 28, 1998 by Lias Carnahan, NIST

Notes on Feb 15, 1999 by X. Ma (maxi@cs.cornell.edu)

Goals

To develop cross-disciplinary requirements for real-time functionality that is needed by real-time java application

Representative Group Members

NIST, IBM, SUN, HP, Honeywell, Motorola, Microsoft, TeleMediaDevices, NewMonics, etc.

Real-Time Concept

Timeliness

Predictability

Hard/Soft time constraint

Hard/Soft real-time computing

Java Traits

Higher level of abstraction for increased programmer productivity

Secure: keeping software components protected from one another

Dynamic loading, integration, reuse, and distributed application

Portable: 100% pure java

Examples of Agreements

RTJ may compromise simplicity with efficiency or performance

RTJ should support creation of reusable software

RTJ should maximize the use of non-RTJ technologies

RTJ must not restrict nor specify the GC technique

RTJ shall provide support for a guaranteed allocation rate

Main Open Consensus

RTJ should both to be pragmatic as well as to provide a direction to the state of the art

RTJ should allow real-time constraints be written into the software

RTJ must support ability to build deadline-based scheduler on top

RTJ should provide "hint handling" information regarding the GC

RTJ should provide for specifying memory

Discussion Points

What does real-time computing involve?

Should Real Time JVM be made 100% pure?

Can JVM for Java 2 do some real-time jobs?

Is Just-In-Time (JIT) compiler ready for real-time java?

What is the difference between traditional GC and real-time GC?

What is the latest news on RTJ? After recent release of Embedded Java 1.0, SUN is going to announce real-time extensions to support RTJ. What is the impact on the real-time software business?

What is the response from Microsoft?