Patent ID: 6189078
Filing Date: 2001-02-13
Classification: G06F

Abstract:
A method for reducing data transfer delays in a transaction processing system which includes a plurality of devices each having an associated local memory, and a supervisory memory module having a main storage module for storing data segments and a directory storage for maintaining ownership status of each data segment stored in the main storage module and the local memories, wherein a first one of the devices includes a first local memory storing a copy of a data segment requested by a second one of the devices, the method comprising:transferring a data transfer request for the requested data segment from the second device to the supervisory memory module, wherein the data transfer request includes an identifier requesting permission to modify the requested data segment;delivering the requested data, and a data transfer response, to the second device upon receipt of the data transfer request, wherein the data transfer response provides modification privileges of the requested data segment to the second device;issuing a purge command to the first device to invalidate the copy of the requested data segment in the first local memory;delivering a purge acknowledge response to the second device upon issuance of the purge command to the first device, wherein the purge acknowledge response provides an indication that the copy of the requested data in the first local memory has been invalidated.