Monitoring Mendix Runtime

Last update: Edit

1 Introduction

For on-premises and local deployments of Mendix, the Mendix Runtime monitoring actions can be called by sending a JSON request to the admin handler. This is accomplished by sending a request to the admin port which is specified in the application configuration (the default port is 8090).

You can change the admin port from Studio Pro by navigating to Project > Settings > Configurations > your configuration > Server > Admin port.

The request needs to be of the POST type with No Authorization and the following headers:

  • Content-Type: application/json
  • X-M2EE-Authentication: yourM2EEPassword_Base64Encoded

The M2EE password is NOT the super administrator password, but a separate password. If you have the application deployed on premises, you can set this password in the settings.yaml file, which is located in the Apps/YourProject folder. If you are running the application from Studio Pro, the M2EE password is set automatically by Mendix, and you can retrieve it from the environment variables of your application process.

The next sections explain which monitoring actions are supported.

2 Current Executions

2.1 Request

"{"action" : "get_current_runtime_requests", "params":{} }"

2.2 Example Response

{
  "feedback":{
    "202de1e51639ae0":{
      "request_duration":106175,
      "type":"CLIENT",
      "user":"Anonymous_2ce7c971-f077-4aca-83c5-f3898443ed01",
      "action_stack":[
      {
        "xpath":"//MyFirstModule.Entity",
        "amount":1,
        "depth":0,
        "offset":-1,
        "sort":{},
        "type":"RetrieveXPathAction"
      },
      {
        "current_activity":{
          "caption":"Retrieve Entity from database",
          "type":"RetrieveByXPath"
        },
        "name":"MyFirstModule.LoopNested",
        "type":"Microflow"
      },
      {
        "current_activity":{
          "caption":"LoopNested",
          "type":"SubMicroflow"
        },
        "name":"MyFirstModule.Loop",
        "type":"Microflow"
      }
    ]},
    "bcbb5508-0293-4f12-b290-ee109962811e":{
      "request_duration":104776,
      "type":"CLIENT_ASYNC_MONITORED",
      "user":"Anonymous_2ce7c971-f077-4aca-83c5-f3898443ed01",
      "action_stack":[
      {
        "current_activity":{
          "caption":"Retrieve Entity from database",
          "type":"RetrieveByXPath"
        },
        "name":"MyFirstModule.LoopNested",
        "type":"Microflow"
      },
      {
        "current_activity":{
          "caption":"LoopNested",
          "type":"SubMicroflow"
        },
        "name":"MyFirstModule.Loop",
        "type":"Microflow"
      }
    ]}
  },
  "result":0
}

2.3 Return Values

This request returns the current executions of actions known by the Mendix Runtime. Actions can include microflows, Java actions, web service calls, and scheduled events. For each execution the following is reported:

  • The “duration” of the execution in milliseconds
  • The “type” of execution. Possible types are:
    • “CLIENT”
    • “CLIENT_ASYNC” – the asynchronous microflow call triggered from the web client
    • “CLIENT_ASYNC_MONITORED” – the actual execution of the asynchronous microflow in the Mendix Runtime, which happens in a different thread from CLIENT_ASYNC
    • “CUSTOM”
    • “WEB_SERVICE”
    • “SCHEDULED_EVENT”
    • “UNKNOWN”
  • The “user” associated with the session executing the action – for a non-user session the name “System” is returned
  • The “action_stack” for this execution – for each action in this stack detailed information is displayed, for example the current activity and name of a microflow

3 Runtime Statistics

3.1 Request

"{"action" : "runtime_statistics", "params":{} }"

3.2 Example Response

{
  "feedback":
  {
    "requests":
    [
      {"name":"","value":97,"last_request_timestamp":1394785085325},
      {"name":"file","value":0,"last_request_timestamp":1394785072325},
      {"name":"ws-doc/","value":0,"last_request_timestamp":1394785072325},
      {"name":"xas/","value":8,"last_request_timestamp":1394785082325},
      {"name":"ws/","value":0,"last_request_timestamp":1394785072325}
    ],
	"cache": { "total_count":2 },
    "sessions":
    {
	  "user_sessions":{
        "562949953421313":[
          "Mozilla/5.0 (Windows NT 6.3; WOW64; rv:39.0) Gecko/20100101 Firefox/39.0"
        ]
      },
      "named_users":3,
      "named_user_sessions":1,
      "anonymous_sessions":0
    },
    "connectionbus":
    {
      "update":7,
      "transaction":0,
      "select":28,
      "delete":5,
      "insert":5
    },
    "memory":
    {
      "code":0,
      "init_nonheap":2555904,
      "init_heap":268435456,
      "eden":0,
      "memorypools":[
        {
          "is_heap":false,
          "usage":11788032,
          "name":"Code Cache",
          "index":0
        },
        {
          "is_heap":false,
          "usage":49590256,
          "name":"Metaspace",
          "index":1
        },
        {
          "is_heap":false,
          "usage":6458552,
          "name":"Compressed Class Space",
          "index":2
        },
        {
          "is_heap":true,
          "usage":106799624,
          "name":"PS Eden Space",
          "index":3
        },
        {
          "is_heap":true,
          "usage":0,
          "name":"PS Survivor Space",
          "index":4
        },
        {
          "is_heap":true,
          "usage":18500976,
          "name":"PS Old Gen",
          "index":5
        }
      ],
      "committed_heap":301465600,
      "max_heap":3817865216,
      "used_nonheap":67844048,
      "max_nonheap":-1,
      "committed_nonheap":72777728,
      "used_heap":125300600
  },
  "result":0
}

3.3 Return Values

3.3.1 Requests

Displays information about the request per handler:

  • The empty handler represents the resource request handler, which handles images, forms etc. (only in use when no reverse proxy is used for static content handling).
  • “file” handles file uploads and downloads
  • “xas/” processes CRUD actions and microflow execution calls issued by the web client
  • “ws/” and “ws-doc/” handle web service requests and provide web service documentation

For each handler you will get two pieces of information:

  • The value field shows the number of requests per handler.
  • The last_request_timestamp field shows the timestamp in milliseconds of the last handled request. If there are no requests handled, this field shows the moment the handler is registered.

3.3.2 Cache

Shows the total number of objects which are currently part of the runtime state (all session together). The runtime state either resides in memory (non-clustered runtime) or in Redis or the database (clustered runtime). Too many objects in the state could slow down the performance of the Mendix Runtime.

3.3.3 Sessions

The “user_sessions” sections shows the current user sessions with their user agents.

The other sections show the number of sessions per category. Categories are:

  • “named users” (the number of user instances)
  • “named_user_sessions” (the number of non-anonymous concurrent sessions)
  • “anonymous_sessions” (the number of anonymous concurrent sessions)

3.3.4 Connectionbus

Number of database requests. Distinguishes between “select”, “update”, “insert”, and “delete” commands and started database transactions.

3.3.5 Memory

Represents the number of bytes allocated to the specified memory sections. For a general explanation, see the Oracle documentation on tuning garbage collection. For the heap and non-heap fields see the memory usage page.

The “memorypools” section contains an ordered list of all the memory pools exactly as we receive them from the JVM with some fields of the MemoryPoolMxBean:

  • “usage” – returns an estimate of the memory usage of this memory pool (in bytes)
  • “is_heap” – is this memory pool part of the heap or not?
  • “name” – the description of the memory pool as received by the JVM. These names can be different depending on for example JDK,memory manager or garbage collection options
  • “index” – the index in the JSON Array. This field is not strictly needed as the pools are returned in a list so you can, and should, rely on the order of the list in case you are processing them in a program

4 State Statistics

4.1 Request

"{"action" : "cache_statistics", "params":{} }"

4.2 Example Response

{
  "feedback":{
    "totals":{
      "Expenses.TempUser":1,
      "System.Session":1
    },
    "user_totals":[
      {
        "user_name":"MxAdmin",
        "total_count":2,
        "amounts_per_type":{
          "Expenses.TempUser":1,
          "System.Session":1
         }
      }
    ]
  },
  "result":0
}

4.3 Return Values

This monitoring action gives more detailed information about objects which are currently in the state of the Mendix Runtime:

  • “totals” shows the total number of objects per sessions is shown
  • “user_totals” shows the number of objects per entity for a particular sessions

This information can be an aid in figuring out which objects cause a lot of memory usage.

5 Server Statistics

5.1 Request

"{"action" : "server_statistics", "params":{} }"

5.2 Example Response

{
  "feedback":{
    "jetty":{
      "current_connections":0,
      "max_connections":0,
      "max_idle_time_s":200
    },
    "threadpool": {
      "idle_threads":3,
      "max_threads":254,
      "threads_priority":5,
      "threads":8,
      "max_queued":-1,
      "min_threads":8,
      "max_idle_time_s":60,
      "max_stop_time_s":0
    }
  },
  "result":0
}

5.3 Return Values

The server statistics monitor action gives information about the embedded Jetty web server. The “jetty” section lists the number of current open connections and the maximum number of open connections. In addition, it lists the maximum idle time of the connection before it is closed, if Jetty is running under normal circumstances.

The “threadpool” section gives information about the threadpool of the handler which processes all requests which go through the runtime port. See the Jetty QueuedThreadPool documentation for more information.

6 Logged-In Users

6.1 Request

"{"action" : "get_logged_in_user_names", "params":{} }"

6.2 Example Response

{
  "feedback": {
    "count":1,
    "users":["MxAdmin"]
  },
  "result":0
}

6.3 Return Values

Shows which users are currently logged in. If a user has multiple sessions, this user will be listed once for every session.

7 Thread Stack Traces

7.1 Request

"{"action" : "get_all_thread_stack_traces", "params":{} }"

7.2 Example Response

{
  "feedback": {
    "qtp1967003817-95":[
      "sun.misc.Unsafe.park(Native Method)",
      "java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)",
      "java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)",
      "java.util.concurrent.LinkedBlockingQueue.poll(LinkedBlockingQueue.java:467)",
      "com.mendix.modules.microflowengine.debugger.internal.EventPusher.handleRequest(EventPusher.scala:18)",
      "com.mendix.modules.microflowengine.debugger.internal.DebuggerHandler.processJsonRequest(DebuggerHandler.scala:124)",
      "com.mendix.modules.microflowengine.debugger.internal.DebuggerHandler.processRequest(DebuggerHandler.scala:50)",
      "com.mendix.externalinterface.connector.MxRuntimeConnector$1.execute(MxRuntimeConnector.java:69)",
      "com.mendix.externalinterface.connector.MxRuntimeConnector$1.execute(MxRuntimeConnector.java:66)",
      "com.mendix.util.classloading.Runner.doRunUsingClassLoaderOf(Runner.java:32)",
      "com.mendix.externalinterface.connector.MxRuntimeConnector.processRequest(MxRuntimeConnector.java:72)",
      "com.mendix.core.impl.MxRuntimeImpl.processRequest(MxRuntimeImpl.java:715)",
      "com.mendix.m2ee.appcontainer.server.handler.RuntimeHandler.handle(RuntimeHandler.java:41)",
      "org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52)",
      "org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)",
      "org.eclipse.jetty.server.Server.handle(Server.java:368)",
      "org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:489)",
      "org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:942)",
      "org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:1004)",
      "org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:647)",
      "org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:235)",
      "org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)",
      "org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:628)",
      "org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:52)",
      "org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608)",
      "org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543)",
      "java.lang.Thread.run(Thread.java:745)"
    ],
    "pool-1-thread-10":[
      "sun.misc.Unsafe.park(Native Method)",
      "java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)",
      "java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)",
      "java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1088)",
      "java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)",
      "java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)",
      "java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)",
      "java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)",
      "java.lang.Thread.run(Thread.java:745)"
    ],
  },
  "result":0
}

7.3 Return Values

Returns all the current thread stack traces by name. This is useful for low level analysis of what is happening in the application. Use the “get_current_runtime_executions” request to retrieve information at a higher level (microflows and other actions).

8 Runtime Status

8.1 Request

"{"action" : "runtime_status", "params":{} }"

8.2 Example Response

{
  "feedback":{
    "status":"running"
  },
  "result":0
}

8.3 Return Values

Returns the current Mendix Runtime status. Possible status values are:

  • “created”
  • “starting”
  • “broken”
  • “running”
  • “stopping”
  • “stopped”

This information can be used to track what state the Mendix Runtime is in when the command to start or stop was given, or to check whether the runtime is still running.

9 Check Health

9.1 Request

"{"action" : "check_health", "params":{} }"

9.2 Example Response

{
  "feedback":{
    "health":"sick",
    "diagnosis": "Remote product web service is offline"
  },
  "result":0
}

9.3 Return Values

In Mendix Studio Pro, a health check microflow can be configured. This microflow can report on the functional status of the application; does the general functionality of the application work, and are the necessary remote services available?

If a health check microflow has been configured, this request will report on the current health status. The “health” value can be one of “healthy”, “sick”, or “unknown” (when no health microflow was configured). For the value “sick,” the “diagnosis” value will give the reason the application is not healthy. This reason is the return value of the health check microflow.

The health check microflow gets invoked multiple times per minute. Therefore, it is recommended to make it light-weight and run quickly. Heavy operations may have a significant impact on your application’s performance.

10 About Runtime

10.1 Request

"{"action" : "about", "params":{} }"

10.2 Example Response

{
   "feedback":{
      "model_version":"unversioned",
      "copyright":"Copyright © 2003-2016 Mendix bv. All rights reserved.",
      "build":"unreleased",
      "vendor":"Mendix",
      "name":"Mendix Runtime",
      "java_version":"1.8.0_77",
      "xasid":"68ece856-3771-4024-9c42-078aaa2282aa",
      "version":"unreleased"
   },
   "result":0
}

10.3 Return Values

Returns feedback about the Mendix Runtime.