public static void scanChanges() {
        MONITOR_INSTANCES.forEach(group -> {
            try {
                group.checkAndNotify();
            } catch (Throwable t) {
                log.error("Files change detection failure, gourp = ", t);
            }
        });
    }
One file changed will cause all related files loaded from the disk again with lastModifiedTimestamp updated.
oap-server/server-library/library-util/src/main/java/org/apache/skywalking/oap/server/library/util/MultipleFilesChangeMonitor.java