Rapid increase in speed and availability of global-network is opening up the possibilities of globally-distributed supercomputing, including our Ninf system. However, performance characteristics of these systems have been little investigated, especially under multi-clients, multi-sites situations.

In order to establish methodology to schedule multiple job requests to multiple computational servers effectively and guarantee performance per each client, we conducted benchmarks under various WAN environments. There, we observed that communication bandwidth dominated performance for communication-intensive applications such as Linpack, and aggregate bandwidth could be sustained for multi-clients located at different internet sites.

Based on these observations, we propose the need for a simulation model based on queuing theory. And we also performed preliminary benchmarks using our scheduling server, called the Ninf Metaserver.

We also report on our collaborative efforts in bridging Ninf with NetSolve, a similar system being developed at Univ. of Tennessee/ORNL.