Abstract. The organization of memory in modern multi-core multiprocessor systems causes the problem of false split of CPU cash string addressed in the paper. The false CPUs cache lines split makes tasks scheduled to be run in parallel by several cores, are executed sequentially. The problem is difficult to detect, and its presence can cause a sharp degradation of the system performance. Programming patterns which give rise to the problem are identified. The templates execution time is measured in the presence of false splitting and after applying the methods proposed in the work to solve the problem. The effect of the number of threads running in parallel on the speed-up of programming templates execution and the efficiency of utilization of the system computing resources are analyzed. It is shown experimentally that the false split significantly affects temporal characteristics of multi-threaded applications. Several methods to eliminate the difficulties are proposed.

Keywords: multiprocessor systems, cache memory, false splitting, multi-threaded application

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