docs: private boolean checkSync() {
          boolean sync = false;
          long last = lastSubmitTime;
          long now = Clock.currentTimeMillis();
          if (last + SYNC_DELAY_MS < now) {
              CONSECUTIVE_SUBMITS.set(this, 0);
          } else if (CONSECUTIVE_SUBMITS.incrementAndGet(this) % SYNC_FREQUENCY == 0) {
              sync = true;
          }
          lastSubmitTime = now;
          return sync;
      }