Porting Ncube Packages to iPSC/860 and iPSC/2 Hypercubes
Jingwen Wang, Mo Mu · Purdue e-Pubs (Purdue University System) · 1991
This report collects the experiences in porting the Sparse Matrix Solver of the Pellpack from Ncube!2 to Intel hypercubes.The differences between these machines are discussed and some important machine dependent issues are raised and solved.A Ncube/2 library has been installed on the Intel iPSC/2 and iPSC/860.Steps to run Ncube/2 code on the Intel hypercubes are listed for both the specific Sparse Mattix Solver package and general Ncube12 programs. Machine FeaturesWe are not going to give a detailed description of these machines as they could be found in many documents listed.at the end of this report.We just want to compare them and show the similarities and differences between them. Host SystemBoth iPSC/2 and iPSC/860 have the PC/386 as their host machine.This host is too slow compared with the Sun/4 host of the Ncubel2.Users have been complaining about the speed and software environment of this host.First, it is slow in compiling code, loading the nodes and controlling input and output of hypercube.Second, the modest Unix System V support on this machine makes it difficult to develop sophisticated software environment.There is even no on-line manual on this host.Also, no news and X-window is now supported on this host.One solution to this is to use the remote host support of Intel hypercubes.Sun work-stations can be used as the remote host of the system so that software development can be done partly on the remote host and the user does not need to log into the PC/386 machine to use the hypercube.However, this facility is currently not supported by our iPSC/860 system.The other way is to mount the PC/386 host's file system into the Network File System (NFS).In this way, files on the 386 host can be accessed transparently by any Sun in the cluster as if they were on the same machine.The Caltech iPSC/860 system has been using this approach.Node Processors The Ncube uses its own custom VLSI chips as node processors.The iPSC/2 uses 80386/80387 pair as a node processor, called CX node.A fast scalar processor Weitek 1I 67 can be included optionally on each node to fonn a so-called SX node.Another