Hi, all We would like to discuss our inter-VM shared memory communications proposal with the BPF community. First, VMM (virtual machine monitor) offers significant advantages over native machines when VMs co-resident on the same physical host are non-competing in terms of network and computing resources. However, the performance of VMs is significantly degraded compared to that of native machines when co-resident VMs are competing for resources under high workload demands due to high overheads of switches and events in host/guest domain and VMM. Second, the communication overhead between co-resident VMs can be as high as the communication cost between VMs located on separate physical machines. This is because the abstraction of VMs supported by VMM technology does not differentiate whether the data request is coming from co-resident VMs or not. More importantly, when using TCP/IP as the communication method, the overhead of the Linux networking stack itself is also significant. Although vsock already offers an optimized alternative of inter-VM communications, we argue that lack of transparency to applications is the reason why vsock is not yet widely adopted. Instead of introducing more socket families, we propose a novel solution using shared memory with eBPF to bypass the TCP/IP stack completely and transparently to bring co-resident VM communications to optimal. We would like to discuss: - How to design a new eBPF map based on IVSHMEM (Inter-VM Shared Memory)? - How to reuse the existing eBPF ring buffer? - How to leverage the socket map to replace tcp_sendmsg() and tcp_recvmsg() with shared memory logic? Thanks. Cong
