Collective Operation Resilience for Chiplet-Based UALink Networks

A method for recovering from a chiplet station fault in an Ultra Accelerator Link (UALink)-based network, comprising:

• detecting a fault on a station of a chiplet die, the chiplet die comprising stations coupled to an accelerator die via a die-to-die interface;
• identifying, by a centralized controller, group table entries on one or more switches that reference accelerators coupled to the faulted station;
• updating, by the centralized controller, the identified group table entries to exclude the accelerators coupled to the faulted station;
• and
• redistributing, by the accelerator die, transaction layer flits from the faulted station to operational stations on the chiplet die or on other chiplet dies coupled to the accelerator die.

A system for an Ultra Accelerator Link (UALink)-based network, comprising:

• an accelerator die coupled to a plurality of chiplet dies, each chiplet die coupled to the accelerator die via a separate die-to-die interface, each chiplet die comprising one or more stations with UALink-based ports;
• and
• a centralized controller coupled via an out-of-band management interface;
• wherein upon a fault affecting a first chiplet die or a station on the first chiplet die:
• the accelerator die redistributes transaction layer flits from the affected stations on the first chiplet die to operational stations on one or more other chiplet dies of the plurality of chiplet dies;
• and
• the centralized controller updates forwarding entries on switches in the network to reflect the changed connectivity, routing traffic destined for accelerators previously reachable via the first chiplet die through alternative paths via the other chiplet dies.