Patent ID: 7237068

Claim:
A method for prefetching data in a multiprocessing computer system comprising: a first cache receiving a request to access a first line of data, wherein the request to access the first line of data is a read request; determining that a cache miss with respect to the first line occurred; and transmitting a bundled transaction on a system interconnect in response to the cache miss, wherein the bundled transaction combines a request for the first line of data and a prefetch request, and wherein the bundled transaction includes a bit-map indicating selected lines of data beyond the first line to be prefetched in response to the prefetch request; wherein, in response to the bundled transaction, the method further comprises: determining that a second cache is an owner of the first line of data; determining whether the second cache is also an owner for any of the selected lines of data beyond the first line; the second cache transmitting to the first cache any of the selected lines for which the second cache is an owner; and the second cache transmitting a null-data packet to the first cache for each of a remainder of the selected lines of data for which the second cache is not an owner.