Abstract: A computer system includes a first computing node and a second computing node. The first computing node includes a first device and a first memory. The second computing node includes a second device and a second memory. The first memory includes a first memory space. The second memory includes a second memory space. The first device obtains a cross-node read instruction. The cross-node read instruction includes a virtual address of the second memory space and a size of first data. The first device determines an identifier (ID) of the second computing node based on the virtual address of the second memory space and a first correspondence, to obtain a first network transmission packet, and sends the packet to the second device. The second device receives the packet, reads the first data from the second memory space, and sends the first data to the first device.

Abstract: One example method includes receiving network topology information delivered by a topology manager, where the data center includes a plurality of servers, a plurality of electrical switches, and at least one optical cross-connect device. A data flow can be obtained. A routing policy can be configured for the data flow based on the network topology information, where the routing policy includes any one or a combination of the following routing policies: a first routing policy, where the first routing policy indicates to forward the data flow through an optical channel in the at least one optical cross-connect device; a second routing policy, where the second routing policy indicates to split the data flow into at least two sub-data flows for forwarding; or a third routing policy, where the third routing policy indicates to forward the data flow through an electrical switch of the plurality of electrical switches.