When Elasticsearch starts up, plugins are loaded based on their inter-dependencies. The specific order used is sometimes useful to see. Currently though the actual order cannot be seen. Instead the modules and plugins are logged in name sorted order after all loading has occurred.

We should be more clear about what order the plugins are actually loaded in, though we do need to be careful as to not add too much noise. I suggest moving the "loaded xxx module" message to the actual loading method in PluginsService (it will require passing through whether the code being loaded is a module or plugin).


server/src/main/java/org/elasticsearch/plugins/PluginsService.java
throw new AssertionError(new IOException(e));
        }
    }
    static final String toPackageName(String className) {
        assert className.endsWith(".") == false;
        int index = className.lastIndexOf(".");
        if (index == -1) {
            throw new IllegalStateException("invalid class name:" + className);
        }
        return className.substring(0, index);
    }
    @SuppressWarnings("removal")
    private static void privilegedSetContextClassLoader(ClassLoader loader) {
        AccessController.doPrivileged((PrivilegedAction<Void>) () -> {
            Thread.currentThread().setContextClassLoader(loader);
            return null;
        });
    }
    @SuppressWarnings("removal")
    static Controller privilegedDefineModulesWithOneLoader(Configuration cf, List<ModuleLayer> parentLayers, ClassLoader parentLoader) {
        return AccessController.doPrivileged(
            (PrivilegedAction<Controller>) () -> ModuleLayer.defineModulesWithOneLoader(cf, parentLayers, parentLoader)
        );
    }
    @SuppressWarnings("removal")
    static ClassLoader privilegedFindLoader(ModuleLayer layer, String name) {
        return AccessController.doPrivileged((PrivilegedAction<ClassLoader>) () -> layer.findLoader(name));
    }
}