Dynamic load adaption in LIPS

LiPS 1 is a system for distributed computing using idle-cycles in heterogeneous networks of workstations. Especially data-and compute-intensive applications in the eld of cryptography and computer algebra have used the system. The system provides its user with the tuple space based generative communication paradigm of parallel computing as known from the coordination language Linda 2. In LiPS, failures (fail stop failures) like crashed machines are handled transparently for the application. Dynamic Load Adaption, meaning removing application processes from machines not being idle any longer and migrating those processes to idle machines is based on the detection of crashed application processes and the (re)start of application processes on an idle machine. The implementation of Dynamic Load Adaption is easy, because checkpoint generation and the restart from a checkpoint in LiPS applications is independent from the other application processes. As the crash of an application process (assuming the machine and the operating system the application process resides survive) can be detected very fast, the used mechanism allows for fast adaption of the applications distribution to changes in the NOW availability.