Accession Number:

ADA259417

Title:

Concurrent Smalltalk on the Message-Driven Processor

Descriptive Note:

Technical rept.

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB

Personal Author(s):

Report Date:

1991-09-01

Pagination or Media Count:

241.0

Abstract:

Million-transistor processors are being manufactured today, and soon it will be possible to put several million transistors on one integrated circuit. While memory applications of this technology are clear, it is not obvious how best to use it for computation purposes. One possibility is the architecture of the Message-Driven Processor MDP, which consists of a 324-bit CPU, memory, and a network interface together on one chip. MDPs can be connected directly to each other to form a 65536-processor, message-passing, MIMD, parallel computer, the J-Machine. The MDPs architecture is unusual in that it provides a very high processing power to memory ratio. Concurrent Smalltalk is the primary language used for programming the J-Machine. Concurrent Smalltalk is the language of choice because it fits the J-Machines fine-grain, message- passing model well. This thesis describes Concurrent Smalltalk and its implementation on the J-Machine, including the Optimist II compiler and Cosmos operating system. Optimist II can perform global optimization of programs, including inline function expansion, type inference, and global evaluation of constant expressions. Next, Cosmos and the Concurrent Smalltalk runtime environment are described. Finally, some quantitative and qualitative results are presented. The grain size the average amount of time a method executes before suspending was found to be about 60 instructions, and the MDP was found to execute one instruction every two or four cycles, depending on whether external DRAM is used. A number of qualitative issues are described, along with a few preliminary results for addressing difficult problems such as controlling parallelism....Compiler, Message passing, Parallel processing, Object oriented.

Subject Categories:

  • Electrical and Electronic Equipment
  • Computer Programming and Software
  • Computer Hardware

Distribution Statement:

APPROVED FOR PUBLIC RELEASE