Computer system including a promise array

A computer system comprising:

• a system memory;
• a first active device configured to access data stored in said system memory, wherein the first active device includes a first cache configured to store data accessed by said first active device, and wherein said first active device includes a promise array that stores information identifying an unreceived data packet;
• an address network for conveying address transactions between said first active device and said system memory;
• a data network for conveying data transactions between said first active device and said system memory;
• wherein an access right corresponding to a given block allocated in said first cache transitions in response to a corresponding data packet being received by said first cache through said data network;
• and
• wherein said first active device is configured such the said first active device has an invalid access right to a cache block corresponding to the unreceived data packet for at least a portion of time during which said first active device is an owner of the cache block.

A computer system comprising:

• a system memory;
• a first active device configured to access data stored in said system memory, wherein the first active device includes a first cache configured to store data accessed by said first active device, and wherein said first active device includes a promise array that stores information identifying an unreceived data packet to be conveyed to another device in response to a pending transaction corresponding to a cache block for which said first active device is an owner;
• an address network for conveying address transactions between said first active device and said system memory;
• a data network for conveying data transactions between said first active device and said system memory;
• wherein the first active device is configured such that an access right corresponding to said cache block allocated in said first cache transitions in response to the data packet subsequently being received by said first cache through said data network.