Multiple computers

Grid Computing

• Generally, each node performs a different task/application

• Generally, more heterogeneous

  • Geolocationally, sometimes across regions / companies / institutions

  • In terms of hardware components

• (job schedulers)

  • Oracle Grid Engine / Sun Grid Engine (SGE) / Computing in Distributed Networked Environments (CODINE) / Global Resource Director (GRD)

  • Univa Grid Engine (UGE)

Cluster Computing

• Generally, all nodes perform same/similar tasks

• Generally, more homogeneous

  • Usually connected by LAN

  • Geolocationally, often same server stack

• May be viewed as a single computer at times

Single Computer

• Multiprocessing: Using >1 (Cores of) CPUs

• Multithreading: Using only one (core of) CPU

  • Interleaved/Temporal multithreading

    • Coarse-grained / block / cooperative multithreading: Run till you need to wait (say, for memory), then I’ll let other thread run

    • Interleaved multithreading: you walk a step, then someone else, then you, then someone else…

  • Simultaneous multithreading (SMT): exploit parallelism available across multiple threads to decrease the waste associated with unused issue slots

• General-purpose computing on graphics processing units (GPGPU)