| Popis: |
An efficient implementation of the Process Management Interface (PMI) is crucial to enable a scalable startup of MPI jobs. We propose three extensions to the PMI specification: a ring exchange collective, a broadcast hint to Put, and an enhanced Get. We design and evaluate several PMI implementations that reduce startup costs from scaling as O(P) to O(k), where k is the number of keys read by the processes on each node and P is the number of processes. Our experimental evaluations show these extensions can speed up launch time of MPI jobs by 33% at 8,192 cores. |
