Reliable communication between multi-processor clusters of multi-cluster computer systems

An apparatus for detecting errors in a computer system comprising a plurality of clusters, each cluster including a plurality of local nodes and an interconnection controller interconnected by point-to-point intra-cluster links, communications between the local nodes and the interconnection controller made via an intra-cluster protocol using intra-cluster packets, the interconnection controller of each cluster interconnected by point-to-point inter-cluster links with the interconnection controller of other clusters, the apparatus comprising:

• means for forming an inter-cluster packet by encapsulating an intra-cluster packet;
• means for encoding a sequence identifier in the inter-cluster packet;
• means for calculating first cyclic redundancy code check data based only upon the inter-cluster packet;
• means for encoding the first cyclic redundancy code check data in the inter-cluster packet;
• and
• means for transmitting the inter-cluster packet from a first interconnection controller to a second interconnection controller on a point-to-point inter-cluster link.

A computer system, comprising:

• a first cluster including a first plurality of processors and a first interconnection controller, the first plurality of processors and the first interconnection controller interconnected by first point-to-point intra-cluster links;
• and
• a second cluster including a second plurality of processors and a second interconnection controller, the second plurality of processors and the second interconnection controller interconnected by second point-to-point intra-cluster links, the first interconnection controller coupled to the second interconnection controller by point-to-point inter-cluster links, communications on the first and second intra-cluster links made via an intra-cluster protocol by intra-cluster packets;
• wherein the first interconnection controller is configured to:
• receive an intra-cluster packet from a first processor in the first plurality of processors;
• store the intra-cluster packet in a buffer;
• add a header, including a sequence identifier, to the intra-cluster packet to form a high-speed link packet;
• compute a first cyclic redundancy code check based only upon the high-speed link packet;
• encode first cyclic redundancy code check data in the high-speed link packet;
• and
• transmit the high-speed link packet to the second interconnection controller in the second cluster;
• wherein the second interconnection controller is configured to:
• receive the high-speed link packet;
• compute a second cyclic redundancy code check based only upon the high-speed link packet;
• compare results of the second cyclic redundancy code check with the encoded first cyclic redundancy code check data in the high-speed link packet;
• and
• notify the first interconnection controller regarding the results of the comparison.

An interconnection controller, comprising:

• an intra-cluster interface configured for coupling with intra-cluster links to a plurality of local processors arranged in a point-to-point architecture in a local cluster;
• an inter-cluster interface configured for coupling with an inter-cluster link to a non-local interconnection controller in a non-local cluster;
• a transceiver configured to:
• receive an intra-cluster packet from a local processor via an intra-cluster link;
• encode a sequence identifier in a header of the intra-cluster packet;
• compute cyclic redundancy code check data based only on the encoded packet;
• and
• encode the cyclic redundancy code check data in the encoded packet;
• and
• a serializer/deserializer configured to serialize the encoded packet and forward the encoded, serialized packet to the inter-cluster interface for transmission to the non-local interconnection controller via an inter-cluster link.