Integrating Kernel Activations in a Multithreaded Runtime System on Top of LINUX

Clusters of SMP machines are frequently used toperform heavy parallel computations, and the concepts of multithreading have proved suitable for exploiting SMP architectures. Generally, the programmer uses a thread library to write this kind of program. Such a library schedules the threads or asks the OS to do it, but both of these approaches have problems. Anderson et al. have introduced another approach which relies on cooperation between the OS scheduler and the user application using activations and up calls. We have modified the LINUX kernel and adapted the MARCEL thread library (from the programming environment PM2) to use activ ations. Improved performance w as observed and problems caused by blocking system calls were removed.