Product architecture
iStrobe options augment these basic functions by providing support for specific operating environments such as IMS, CICS, or Db2.
The basic iStrobe system is made up of the following functions:
Session management facility
The session management facility enables you to submit and track measurement requests. The facility includes the Session Requester, the Session Manager, and the Strobe Environment.
The Session Requester operates in the user’s address space, where it receives, edits, and directs measurement requests to the session manager. Measurement requests can originate from Strobe/ISPF, include iStrobe, TSO terminals, batch jobs, and system consoles.
The Session Manager receives measurement requests from the session requester. It maintains a Strobe Request Element (SRE) for each measurement request in a local work queue, and records its actions in the Strobe log dataset. If the target application is already executing, the session manager initiates measurement immediately. Otherwise, measurement begins when the application begins executing. The session manager also communicates with the Measurement Services Address Space (MSAS) to process AutoStrobe functions.
The Strobe environment contains the Strobe SVC, attach filter, common control block interfaces, and subsystem interface.
The session management facility utilizes user-provided parameters to control collection of data, such as attribution data for compiler run-time library routines or performance statistics for CICS.
Measurement facility
Strobe collects performance data by deploying a measurement task within the measured address space. Once activated, the measurement task connects to the measure services address space to dynamically allocate a sample dataset and begins sampling. The session manager sends sampling control commands to the measurement task. The measurement task responds to these commands and records its actions with messages sent through the Strobe SVC.
Reporting facility
Following a measurement session, Strobe organizes and analyzes the measurement data and produces the Performance Profile or XML to be sent to iStrobe for viewing. The Performance Profile is a set of reports that shows how user programs and system service routines are using system resources.
The following diagram illustrates the iStrobe workflow.
The numbered steps in a iStrobe workflow include:
- A mainframe Strobe user, iStrobe user, or Workbench for Eclipse user initiates a request for their user application.
- Strobe Session Manager receives the Strobe request and implants a Strobe measurement task in the user's running application.
- The Strobe measurement task passes collected measurement samples to the Measurement Services Address Space (MSAS), which writes them to the Sample Dataset.
- The Strobe Reporting Facility takes the Sample Dataset as input and builds the iStrobe Profile Report.
- The Profile Report is available for display.