Yang YU (yyu@cs.ucsd.edu)
Wed, 17 May 2000 22:06:29 -0700

Lightweight Remote Procedure Call
Light weighted RPC(based on RPC) designed to handle
communication between protected domains on a SINGLE machine.

monolithic kernels: few protection boundaries inside OS itself,
less secure, less modifiable, debuggable.
Capability systeme: fine grained objects sharing the space
address but have own protected domains. But not efficient.
How to solve the problem:
most communications are between domains on the same machine
most communications are simple.
RPC is too expensive to be used to handle local communications.
Lightweight RPC
Simple Control transfer
Simple data transfer
Simple stubs

Their ideas are useful and helpful

Active Messages
Main Ponint:
Active Messages integrates computation and communication so that
the communication overhead is low while the processor performance is

Design Challenge for large - scale mulitprocessors:
(1) lower communication overhead
(2) overlap computation and communication
(3) integrate the two without lost on performance

Traditional approaches:
Message Passing Architecture: more focused on processing,
results in high overhead in communication
Prototype of Message Driven Architectures: hardware resources
are mostly spent on message transmission, reception and scheduling.
Leads to short compuation lengths, which waste the processors's power.
Reasons of slowdown(overlap prevented):
(1) buffering and resource allocation
(2) blocking or delayed service is allowed

Goal of AM:
get data from network and integrate them in to computation as
soon as possible.

allowing sender specify the address of the handler when message
No buffering
Deadlock avoidance
Split-C, CM-5, nCuBe2, TAM
I think this paper is well organized, Find the problem, solve
the problem

Yang Yu
Department of Computer Science and Engineering
University of California, San Diego