System and method for conditionally sending a request for data to a home node
View Patent ↗A system, method, and computer program product are provided for conditionally sending a request for data to a home node. In operation, a first request for data is sent to a first cache of a node. Additionally, if the data does not exist in the first cache, a second request for the data is sent to a second cache of the node. Furthermore, a third request for the data is conditionally sent to a home node.
1. A method of querying a plurality of nodes for data requested by a processor, comprising:
determining that the requested data does not exist in a first cache;
determining that the requested data does not exist in a second cache;
sending a request for the requested data to a node determined to be a home node for a particular memory address associated with the requested data.
2. The method of claim 1 , further comprising determining that the request can be satisfied by the home node.
3. The method of claim 2 , further comprising supplying the requested data to the processor.
4. The method of claim 1 , further comprising, determining that the request cannot be satisfied by the home node.
5. The method of claim 4 , further comprising sending a snoop request to an additional node.
6. The method of claim 5 , further comprising determining that the additional node potentially includes a copy of the requested data.
7. The method of claim 5 , further comprising updating a cache state of the additional node based on the snoop request.
8. The method of claim 5 , further comprising receiving a response to the snoop request at the home node.
9. The method of claim 8 , further comprising supplying the requested data to the processor based on the response received from the snoop request.
10. The method of claim 4 , further comprising sending a snoop request to all local caches in the home node.
11. A system capable of querying a plurality of nodes for requested data, comprising,
a home node associated with a particular memory address associated with the requested data; and
a processor configured to:
determine that the requested data does not exist in a first cache;
determine that the requested data does not exist in a second cache;
send a request for the requested data to the home node.
12. The system of claim 11 , wherein the home node is configured to determine that it can satisfy the request.
13. The system of claim 12 , wherein the home node is configured to supply the requested data to the processor.
14. The system of claim 11 , wherein the home node is configured to determine that it cannot satisfy the request.
15. The system of claim 14 , wherein the home node is configured to send a snoop request to an additional node.
16. The system of claim 15 , wherein the home node is configured to determine that the additional node potentially includes a copy of the requested data.
17. The system of claim 15 , wherein the additional node is configured to update a cache state based on the snoop request.
18. The system of claim 15 , wherein the home node is configured to receive a response to the snoop request from the additional node.
19. The system of claim 18 , wherein the home node is configured to supply the requested data to the processor based on the response received from the snoop request.
20. The system of claim 14 , wherein the home node is configured to send a snoop request to all of its local caches.