Concept for providing access to remote memory
Examples relate to a concept for providing access to remote memory. A network interface controller apparatus comprises circuitry configured to obtain a memory transaction request with respect to memory of a first host hosting the network interface controller apparatus from a second host. The circuitry is configured to translate the memory transaction request to a cache transaction request. The circuitry is configured to provide the cache transaction request to the first host. The circuitry is configured to obtain a response to the cache transaction request from the first host. The circuitry is configured to provide information on the response to the cache transaction request to the second host.
1 . A network interface controller apparatus comprising interface circuitry and processing circuitry, wherein the network interface controller apparatus is configured to communicate with another host via a Compute Express Link (CXL), wherein the processing circuitry includes a snoop agent and is to:
obtain a CXL.mem memory transaction request with respect to memory of a first host hosting the network interface controller apparatus from a second host;
have the snoop agent translate the CXL.mem memory transaction request to a CXL.cache transaction request, wherein the CXL.cache transaction request enables the first host to manage cache coherency for the memory of the first host in a host-bias mode;
provide the CXL.cache transaction request to the first host;
obtain a response to the CXL.cache transaction request from the first host; and
provide information on the response to the CXL.cache transaction request to the second host.
2 . The network interface controller apparatus according to claim 1 , wherein the network interface controller apparatus is to provide remote access to the memory of the first host for the second host.
3 . The network interface controller apparatus according to claim 1 , wherein the processing circuitry is to obtain the CXL.mem memory transaction request via a computer network from the second host, and to provide the information on the response to the CXL.cache transaction request via the computer network to the second host.
4 . The network interface controller apparatus according to claim 3 , wherein the computer network is an ethernet-based computer network.
5 . The network interface controller apparatus according to claim 1 , wherein the processing circuitry is to provide the response to the CXL.cache transaction request to the second host.
6 . The network interface controller apparatus according to claim 1 , wherein the processing circuitry is to translate the response to the CXL.cache transaction request to a response suitable for the CXL.mem memory transaction request, and to provide the response suitable for the CXL.mem memory transaction request as information on the response to the CXL.cache transaction request to the second host.
7 . The network interface controller apparatus according to claim 1 , wherein the processing circuitry is to provide the CXL.cache transaction request to a device coherency agent.
8 . The network interface controller apparatus according to claim 1 , wherein the network interface controller apparatus is configured to provide remote access to the memory of the second host for the first host, wherein the processing circuitry is to:
obtain a further CXL.mem memory transaction request with respect to memory of the second host from the first host;
provide the further CXL.mem memory transaction request to the second host;
obtain information on a response to a further CXL.cache transaction request from the second host in response to the further CXL.mem memory transaction request; and
provide a response suitable for the further CXL.mem memory transaction request to the first host based on the information on the response to the further CXL.cache transaction request.
9 . The network interface controller apparatus according to claim 8 , wherein the processing circuitry is to look up a network address of the second host, and to provide the further CXL.mem memory transaction request to the second host based on the network address of the second host.
10 . The network interface controller apparatus according to claim 9 , wherein the processing circuitry is to look up the network address of the second host from a network address data storage of the network interface controller apparatus.
11 . The network interface controller apparatus according to claim 8 , wherein the processing circuitry is to provide the further CXL.mem memory transaction request via a computer network to the second host, and to obtain the information on the response to the further CXL.cache transaction request via the computer network from the second host.
12 . The network interface controller apparatus according to claim 8 , wherein the information on the response to the further CXL.cache transaction request comprises the response to the CXL.cache transaction request, wherein the processing circuitry is to translate the response to the further CXL.cache transaction request to the response suitable for the CXL.mem memory transaction request.
13 . The network interface controller apparatus according to claim 8 , wherein the information on the response to the further CXL.cache transaction request comprises the response suitable for the CXL.mem memory transaction request.
14 . The network interface controller apparatus according to claim 8 , wherein the network interface controller apparatus is configured to expose the memory of the second host towards the first host as a region of memory of the network interface controller apparatus.
15 . A network interface controller apparatus comprising interface circuitry and processing circuitry, wherein the network interface controller apparatus is configured to communicate with another host via a Compute Express Link (CXL), wherein the processing circuitry includes a memory router and a memory translation table, and is to:
obtain a CXL.mem memory transaction request with respect to memory of a second host from a first host hosting the network interface controller apparatus;
have the memory router look up a network address of the second host in the memory translation table based on the CXL.mem memory transaction request and provide the CXL.mem memory transaction request to the second host based on the network address;
obtain information on a response to a CXL.cache transaction request from the second host in response to the CXL.mem memory transaction request; and
have the memory router translate the information on the response to the CXL.cache transaction request into a response suitable for the CXL.mem memory transaction request and provide the response to the first host.
16 . The network interface controller apparatus according to claim 15 , wherein the network interface controller apparatus is to provide remote access to the memory of the second host for the first host.
17 . A method for a network interface controller, wherein the network interface controller apparatus is configured to communicate with another host via a Compute Express Link (CXL), the method comprising:
obtaining a CXL.mem memory transaction request with respect to memory of a first host hosting the network interface controller from a second host;
translating, by a snoop agent in the network interface controller, the CXL.mem memory transaction request to a CXL.cache transaction request, wherein the CXL.cache transaction request enables the first host to manage cache coherency for the memory of the first host in a host-bias mode;
providing the CXL.cache transaction request to the first host;
obtaining a response to the CXL.cache transaction request from the first host; and
providing information on the response to the CXL.cache transaction request to the second host.
18 . The method for the network interface controller according to claim 17 , wherein the network interface controller is configured to provide remote access to memory of the second host for the first host, wherein the method comprises:
obtaining a further CXL.mem memory transaction request with respect to memory of the second host from the first host;
providing the further CXL.mem memory transaction request to the second host;
obtaining information on a response to a further CXL.cache transaction request from the second host in response to the further CXL.mem memory transaction request; and
providing a response suitable for the further CXL.mem memory transaction request to the first host based on the information on the response to the further CXL.cache transaction request.
19 . A non-transitory machine-readable storage medium including program code, when executed, to cause a machine to perform the method of claim 17 .