A method of executing an algorithm in a parallel manner using a plurality of concurrent threads includes generating a lock-free barrier that includes a variable that stores both a total participants count and a current participants count. The total participants count indicates a total number of threads in the plurality of concurrent threads that are participating in a current phase of the algorithm, and the current participants count indicates a total number of threads in the plurality of concurrent threads that have completed the current phase. The barrier blocks the threads that have completed the current phase. The total participants count is dynamically updated during execution of the current phase of the algorithm. The generating, blocking, and dynamically updating are performed by at least one processor.