private void incForceFlush() {
    Object monitor = getAsyncMonitor();
    synchronized (monitor) {
      getForceFlushCount().incrementAndGet(); // moved inside sync to fix bug
      // 41654
      monitor.notifyAll();
    }
  }
force a flush but do it async (don't wait for the flush to complete).
geode-core/src/main/java/org/apache/geode/internal/cache/DiskStoreImpl.java