文摘
In many cloud computing environments e.g.,Amazons public Elastic Computing Cloud and Open-stack for private clouds),virtual machine VM) instances are the unit of resource allocation. When possible,VM instances can be allocated on the same physical server and many techniques e.g.,using shared memory between VMs) can be used to reduce the overhead of the inter-VM communication. Nahanni is a novel inter-VM shared-memory mechanism. We investigate two inter-VM interprocess communication IPC) mechanisms using Nahanni shared memory. First,minitransactions have different semantics from both traditional shared-memory programming and message-passing programming. We experimentally show that minitransactions can have better performance than traditional lock-based programming under low-contention scenarios. Second,MPI-Nahanni ports the well-known Message-Passing Interface MPI) system to Nahanni. Using microbenchmarks and the GAMESS application,we show how MPI-Nahanni has higher bandwidth and lower latency by up to an order of magnitude or more),and better performance than existing VM-based IPC techniques.