Monitoring - Mendix Runtime - Mendix 6 Reference Guide

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 JSON request should be accompanied by a base64 encoded monitoring password (the password should also be specified in the application configuration) and put in the request header “X-M2EE-Authentication”. The content type of the request should be application/json.

Read the next sections to find out which monitoring actions are supported.

Current Executions

Request

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

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
}

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

The duration of the execution in milliseconds.
The type of execution. Possible types are CLIENT, CLIENT_ASYNC, CLIENT_ASYNC_MONITORED, CUSTOM, WEB_SERVICE, SCHEDULED_EVENT, and UNKNOWN. CLIENT_ASYN is the asynchronous microflow call triggered from the web client, and CLIENT_ASYNC_MONITORED is the actual execution of the asynchronous microflow in the Mendix Runtime, which happens in a different thread.
The user is the name of the user associated with the session executing the action. In case of a non-user session, the name System is displayed.
The action_stack shows the stack of actions for this execution. For each action in this stack, detailed information is displayed (for example, for a microflow, the current activity and the name of the microflow are shown).

Runtime Statistics

Request

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

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
        }
      ],
      "tenured":0,
      "committed_heap":301465600,
      "max_heap":3817865216,
      "survivor":0,
      "used_nonheap":67844048,
      "max_nonheap":-1,
      "committed_nonheap":72777728,
      "permanent":0,
      "used_heap":125300600
  },
  "result":0
}"

Requests Displays information about the request per handler. The value field shows the number of requests per handler. Since Mendix 5.3, 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.

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, and ws/ and ws-doc/ handle web service requests and provide web service documentation.

Cache

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

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), and anonymous_sessions (the number of anonymous concurrent sessions).

Connectionbus

The number of database requests. Distinguishes between select, update, insert, and delete commands and started database transactions.

Memory

Memory statistics should only be interpreted by experts. A lack of detailed knowledge of the Java memory model can lead to false conclusions.

For versions lower than Mendix 6.6 or Mendix 5.21.5 running on Java8, the information returned in the memory part of the response provides incomplete and incorrect information. If you rely on information in this section for these versions, upgrading your version to Mendix 6.7 or 5.21.5 or higher is recommended.

For backwards compatibility reasons, the fields code, eden, tenured, survivor, and permanent are still present, but they should not be relied on anymore. They will be removed from Mendix 7 onwards.

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 Class MemoryUsage. The memorypools section contains an ordered list of all the memory pools exactly as we receive them from the JVM, in the same order and 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, the 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 that you can (and should) rely on the order of the list in case you are processing them in a program.

If you are automatically processing the memorypools section to, for example, display in a graph, you should ideally not make any assumptions about the kind of memory pool based on its order in the list or its name, as these may change depending on, for example, garbage collector settings or the Java version.

In case you do want to develop a strategy for interpreting these pools anyway based on the Java version, you can get the Java version from the about admin action.

State Statistics

Request

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

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
}

This monitoring action gives more detailed information about objects that are currently in the state of the Mendix Runtime. In 1totals, the total number of objects per sessions are shown, and in user_totals the number of objects per entity for a particular sessions are shown. This information can be an aid in figuring out which objects cause a lot of memory usage.

Server Statistics

Request

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

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
}

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, the maximum idle time of connection before it is closed is listed, for both when Jetty is under normal circumstances and when low on resources. Please note that in Mendix 6.10.11 and above, information about the maximum idle time of connections before it is closed when Jetty is low on resources (“max_idle_time_s_low_resources”) is removed as part of the Jetty upgrade, because it is no longer provided by Jetty.

The threadpool section gives information about the threadpool of the handler which processes all requests which go through the runtime port. For more information, see the Jetty QueuedThreadPool documentation.

Logged-In Users

Request

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

Response

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

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

Thread Stack Traces

Request

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

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
}

Returns all the current thread stack traces by name. This is useful to low-level analyze what is happening in the application. Use the get_current_runtime_executions request to retrieve information on a higher level (microflows and other actions).

Runtime Status

Request

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

Response

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

Returns the current Mendix Runtime status. Possible status values are: created, starting, broken, running, stopping, and stopped. This information can be used to track the state the Mendix Runtime is in when the command to start or stop was given or to check whether the runtime is still running.

Check Health

Request

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

Response

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

In the Mendix Modeler, a health microflow can be configured. This microflow can report on the functional status of the application. It will address whether the general functionality of the application works and if the necessary remote services are available.

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

This request can only be executed when the Mendix Runtime status is running (see Runtime Status above).

About Runtime

Request

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

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
}

Returns feedback about the Mendix Runtime. java_version is available from Mendix 6.6 onwards.