Browse Prior Art Database

Diagonal Replacement Scheme to Recover Fault in a Mesh

IP.com Disclosure Number: IPCOM000102782D
Original Publication Date: 1990-Jan-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 48K

Publishing Venue

IBM

Related People

Li, H: AUTHOR

Abstract

Disclosed is a scheme of recovering from a fault in a parallel processor consisting of many processing elements connected by a mesh network.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 73% of the total text.

Diagonal Replacement Scheme to Recover Fault in a Mesh

      Disclosed is a scheme of recovering from a fault in a parallel
processor consisting of many processing elements connected by a mesh
network.

      The disclosed "diagonal replacement scheme" places K extra
spare processing elements in the diagonal of a mesh consisting of KxK
processing elements. The spare processing element at (i, i) location
of the diagonal can replace a faulty element at either location (i,
j) or (j, i).

      To support such a fault recovery, the mesh network needs to be
augmented and an extra replacement circuit is needed. Spare
processing element (i, i), is connected to processing elements (i, s)
and (s, i) for all 1&s&K. The spare processing element (i, i) has
four ports West, East, North and South designated as SW, SE, SN and
SS. These ports are connected to the ports (N, S, E, W) of the
processing elements in the mesh as follows. SW(i, i) is connected to
one of the W(i,s) ports via the replacement circuit while SE(i, i) is
connected to one of the E(i, s) ports, SN(i, i) to one of N(s, i)
ports, and SS(i, i) to one of S(s, i) ports.

      In the situation when no fault is present, the replacement
circuit selects SW, SE, SS and SN not to connect to any ports in the
mesh. When processing element (u, v) is at fault, the replacement
circuit selects SW(u, u) be connected to S(u, v), SE(u, u) to E(u,
v), SN(u, u) to N(u, v) and SS(u, u) to S(u, v) if that spare
processing eleme...