private void regulate(LoadLevel loadLevel, long now) {
        if (LoadLevel.NORMAL.equals(loadLevel)) {
            if (!LoadLevel.NORMAL.equals(lastRegulateLevel)) {
                LOGGER.info("The system is back to a normal state, checkers: {}", loadLevels);
            }
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug("The system is in a normal state, checkers: {}", loadLevels);
            }
        } else {
            LOGGER.info("The system is in a {} state, checkers: {}", loadLevel, loadLevels);
        }

        loadLevel.regulate(regulator);
        lastRegulateTime = now;
        lastRegulateLevel = loadLevel;
    }
Get the current load level of the system, which is, the maximum load level from all checkers.
core/src/main/java/kafka/automq/backpressure/DefaultBackPressureManager.java