Due multithreading we need a merge statistic of operations from the threads for a every period. This is not an obvious task, since the threads could perform a different operations, the length of which can vary greatly. Therefor we need a timeframe for such mergers, and check that statistic from each threads merged single time per frame, and this frame was the same for all threads. Also the implementation should be wait-free and extremely cheap for CPU, otherwise benchmark result would be distorted.
Current implementations seems to be works, but it is unclear, difficult to support and development.
This is most moronic and unclear part of code (aka "говнокод"), which had created extremely fast for http://www.highload.ru/2015/abstracts/1831.html
Due multithreading we need a merge statistic of operations from the threads for a every period. This is not an obvious task, since the threads could perform a different operations, the length of which can vary greatly. Therefor we need a timeframe for such mergers, and check that statistic from each threads merged single time per frame, and this frame was the same for all threads. Also the implementation should be wait-free and extremely cheap for CPU, otherwise benchmark result would be distorted.
Current implementations seems to be works, but it is unclear, difficult to support and development.