READ2: Put disks at network level

Grand challenge applications have to process large amounts of data, and then require high performance IO systems. Cluster computing is a good alternative to proprietary system for building cost effective IO intensive platform: some cluster architectures won sorting benchmark (MinuteSort, Datamation)! Recent advances in IO component technologies (disk, controller and network) let us expect higher IO performance for data intensive applications on cluster. The counterpart of this evolution is that much stress is put on the different buses (memory, IO) of each node which cannot be scaled. In this paper we investigate a strategy we called READ² (Remote Efficient Access to Distant Device) to reduce this stress. With READ² any cluster node accesses directly to remote disk: the remote processor and the remote memory are removed from the control and data path: Inputs/Outputs don´t interfere with the host processor and the host memory activity. With READ² strategy, a cluster can be considered as a shared disk architecture instead of a shared nothing one. This papers describes an implementation of READ² on Myrinet Networks. First experimental results show IO performance improvement.