Definition
The workload overview outputs data about the workload that is written by the SAP kernel and displayed using the workload monitor (transaction ST03N). The workload overview provides system administrators with various detailed information about the most important workload data, such as CPU time, the number of database changes, response times, and so on.
In SAP Basis 4.6C, the workload monitor was extended so that it now also includes GUI times, Frontend network times and the RFC time.
Structure
You can display the workload overview for all task types (Dialog, Background, RFC, ALE and Update) or for one particular task type. The system displays the following data:| Information | Explanation |
| Average CPU Time | Average time that a workprocess uses the CPU; during a dialog step, the CPU of the application server is used for processing (loading, generating, processing database requests, ABAP processing, and so on). The CPU time is determined by the operating system. At the end of a transaction step, the SAP work process queries the CPU time from the operating system. The CPU time is therefore not an additive component of the response time, unlike wait time, roll in time, load time and database time. |
| Average Response Time | Average time between the time at which a dialog process sends a request to a dispatcher work process, and the time at which the dialog is completed and the data is transferred to the presentation layer. The response time does not include the time for transferring the data from the SAP frontend to the application server. For networks with bad performance, a more subjective response time can therefore emerge. The transfer time is included in the GUI time and the Frontend network time. |
| Average Wait Time | The average time an unprocessed dialog step waits in the dispatcher queue for a free work process. Under normal circumstances, the dispatcher work process should pass a dialog step immediately after receiving the request from the dialog step. In this situation, the average wait time should be only a few milliseconds. If the application server of the entire system is under a heavy load, this can lead to traffic jams in the dispatcher wait queue. |
| Average Load and Generation Time | Average time required to load and generate objects such as ABAP source code and screen information from the database. |
| DB Calls | Number of parsed accesses to the database |
| DB Access | Number of logical ABAP accesses to data in the database; these accesses are made through the SAP database interface and are parsed into individual database calls. The ratio of database calls to database accesses is important. If the access to information in a table is buffered in the SAP buffer, no database calls to the database server are required. The ratio of Calls/Accesses therefore gives an indication about the efficiency of the table buffering. A good ratio would be 1:10. |
| GUI Time | Response time between the dispatcher and the Gui during the roundtrips (roundtrips are communication steps between the SAP system and the frontend during a transaction step). |
| Roll Ins | Number of rolled in user contexts |
| Roll Outs | Number of rolled-out user contexts |
| Roll In Time | Processing time for the rolling in of user contexts |
| Roll Out Time | Processing time for the rolling out of user contexts |
| Roll Wait Time | Wait time in the roll area When synchronous RFCs are called, the work process performs a roll out and waits for the end of the RFC in the roll area. The RFC server programs can wait for other RFCs to be sent to them in the roll area. |
| Average Time per Logical Database Call | Average response time for all commands sent to the database system (in milliseconds). The time depends on the CPU capacity of the database server, the network, buffering, and on the input/output capabilities of the database server. The access times for buffered tables are far faster and are not considered here. |
Background information
The response time is usually split into wait time plus execution time. The SAP response time is made up of the following components:
Response Time = Wait Time + Execution Time
where: Execution Time =
+ Load time for programs, screens and the graphical interface
+ Roll times for rolling in the work data
+ ABAP processing time
+ Database time
+ Enqueue time for logical SAP lock processes
+ CPIC/RFC time
+ Roll wait time (excluding Task types RFC/CPIC/ALE)
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