Application Threads Test

The J2EE Engine thread system is responsible for handling system and client threads. It comprises of two managers – Thread Manager and Application Thread Manager. The Application Threads test monitors the Application Thread Manager of the SAP Web Application server, which supplies the threads in which the client applications’ source code is executed. This manager provides a set of properties for starting and managing client threads in the Java Virtual Machine. When a client request comes, the system tries to find a free thread in the Application Thread Manager and to start the execution of the request. If no free thread is available, the thread system buffers the request in a request queue. By buffering the threads and using them again, the system achieves better performance than using normal Java thread system without buffering. The Application Thread Manager runs only on server processes.

Target of the test : A SAP Netweaver Application Server

Agent deploying the test : An internal agent

Outputs of the test : One set of results each for the Dispatcher and each of the configured server processes of the SAP Web AS.

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed

Host

Specify the server for which the test is to be configured.

Port

The port number at which the specified server listens.

UserName

This test connects to a specific SAP web application server instance, and extracts critical metrics from it. Therefore, in the UserName text box, provide a valid j2ee admin user name which the test should use for connecting to the server instance.

Password

Provide the Password that corresponds to the specified UserName.

Confirm Password

Confirm the OS Password by retyping it here.

InstanceName

Provide the name of the application server instance to which the test should connect. For example, if you specify tpp here, then the test will use the login credentials (UserName and Password) provided here to connect to an instance named TPP. To know the available server instances, use the instructions provided in Determining the Name of the SAP Web AS Instance.

ConnectorPort

This test uses the P4 protocol for connecting to the SAP web application server. Therefore, the port at which the P4 protocol listens needs to be specified as the ConnectorPort. To know how to determine the P4 port, use the procedure detailed in Determining the P4 Port.

DispatcherID

This test reports a set of metrics for the Java dispatcher that receives client requests. By default, the cluster ID  of the dispatcher is auto-discovered by the eG Enterprise. Therefore, default option is specified against this parameter. Alternately, if you wish to monitor a specific cluster ID, then you can mention that cluster ID against this parameter. To know the cluster ID of the dispatcher, follow the steps discussed in Determining the Name of the SAP Web AS Instance and P4 Protocol Port .

ServerIDs

Typically, the Java dispatcher or the ICM distributes the client requests it receives to the server processes executing on the Java component of the SAP Web AS for processing.  By default, the ServerIDs are auto-discovered by the eG Enterprise. To monitor specific server processes, specify a comma-separated list of the cluster IDs of these server processes in the ServerIDs text box. To know the cluster IDs of the server processes, follow the procedure detailed in Determining the Name of the SAP Web AS Instance and P4 Protocol Port.

Providing a comma-separated list of server process cluster IDs will ensure that these cluster IDs alone appear as the descriptors of the test. If need be, you can have server process name-cluster ID pairs appear as the test descriptors. To achieve this, the specification in the ServerIDs text box should be of the following format: Server process name:Cluster ID of the server process. For example, if the cluster ID of a server process named Server0 is 12621850, then you can specify the ServerID in the format: Server0:12621850.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Active threads

Indicates the number of threads from the thread pool which are currently executing a runnable task.

Number

This measure serves as a good indicator of the server workload.

Current pool size

Indicates the number of threads that are currently in the thread pool.

Number

 

Threadpool usage

Indicates the percentage of threads in the thread pool that are being currently utilized.

Percent

If the value of this measure is high, it could indicate a heavy server workload.

Waiting tasks

Indicates the number of tasks waiting for threads, so as to begin execution.

Number

 

Tasks queue size

Indicates the capacity of the request queue where the tasks waiting for execution are stored.

Number

 

Task queue overflow

Indicates the number of tasks waiting to be placed in the request queue, in the event that the request queue is full.

Number

If the value of this measure increases consistently, it could indicate a processing bottleneck.