Patent ID: 7756943
Filing Date: 2010-07-13
Classification: G06F

Abstract:
1. A system comprising: a plurality of computers coupled to a network, wherein each of the plurality of computers comprises a memory and a hardware device coupled to the memory, wherein the hardware device is configured to communicate on the network, wherein the hardware device is configured to perform remote direct memory access (RDMA) communications on the network to access the memory in other ones of the plurality of computers; wherein a guest physical address space of a virtual machine formed from the plurality of computers spans at least a portion of the memories in each of the plurality of computers, each of the plurality of computers serving as a home node for at least one respective portion of the guest physical address space; wherein a software module on a first computer of the plurality of computers, when executed on the first computer, uses RDMA to coherently access data on a home node of the data without interrupting execution in the home node; wherein the software module, when executed, accesses the data using a first RDMA operation, and wherein the software module, when executed, uses the guest physical address of the block in the first RDMA operation, and wherein the hardware device in the home node is configured to translate the guest physical address to the corresponding address in the memory in the home node, and wherein the hardware device in the home node is configured to access the memory using the corresponding address; and wherein the access to the data comprises a read operation, and wherein the first RDMA operation is an RDMA read, and wherein the RDMA read includes the guest physical address and further includes a target address in the first computer, the target address identifying a location in the memory of the first computer, and wherein the RDMA read comprises the hardware device in the home node reading data from the corresponding address and transmitting the data to the first computer, and wherein the hardware device in the first computer is configured to write the data to the location in the first computer.