Digital Equipment Corporation

University of Washington

Anna R Karlin

Andrei Z Broder

Chandramohan Amyangot Thekkath

Henry M Levy

William Eugene Morgan

Michael J Feeley

A system and method for managing memory in a network. In a computer network in which multiple computers (nodes) are interconnected by a network, the primary memory on one node may be used to store memory data (pages)from other nodes. The transfer of a data page over the network from the memory of a node holding it to the memory of another node requesting that data gives improved performance when compared to the transfer of the same data from disk, either local or remote, to the requesting node. Global information about the disposition of the nodes and their memories in the network is used to determine the nodes in the network that should best be used to hold data pages for other nodes at a particular time. This information is exchanged by the nodes periodically under command of a coordinating node. The system includes distributed data structures that permit one node to locate data pages stored in another node's memory, procedures to determine when global information should be recomputed and redistributed, and procedures to avoid overburdening nodes with remote page traffic.

Using global memory information to manage memory in a computer network

A data processing system and method particularly useful for network address lookup in interconnected local area networks uses a family of hashing algorithms that allow implementation of a dictionary that is particularly advantageous when the underlying hardware allows parallel memory reads in different memory banks. The system and method requires exactly one memory cycle for deletes and lookup and constant expected amortized cost for insertions. The system and method uses easy-to-compute hash functions and makes no unproven assumptions about their randomness properties, or about any property of keys drawn from a universe U. The system and method makes it possible to build a dictionary that is able to answer 20 parallel searches among 64,000 entries in less than 5 .mu.s using relatively inexpensive hardware.

System with a plurality of hash tables each using different adaptive

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Seattle, WA, United States of America

Anna R Karlin