Patent attributes
Embodiments herein described a coherency protocol for a distributed computing topology that permits for large stalls on various interfaces. In one embodiment, the computing topology includes multiple boards which each contain multiple processors. When a particular core on a processor wants access to data that is not currently stored in its cache, the core can first initiate a request to search for the cache line in the caches for other cores on the same processor. If the cache line is not found, the cache coherency protocol permits the processor to then broadcast a request to the other processors on the same board. If a processor on the same board does not have the data, the processor can then broadcast the request to the other boards in the system. The processors in those boards can then search their caches to identify the data.