Thank you, Roman. The test reveals lack of parallelization in SVS implementation. A single kernel thread processes sequentially sops items using 2 passages: (1) check and (2) apply or block. Then, sops of blocked semop() are checked and possibly resumed. No magic, just lookup, two nested levels—square time complexity with minor heuristics. I invite kernel programmers to the UoD#1 university of the year in the UK PhD program to address the issue and implement greedy semaphores. – Dima