Timing points are trace records (containing identifying and performance data) taken at various points within applications.
Each transaction consists of a number of timing points that form a profile of resource usage and throughput times.
The code to take the timing information is bracketed within conditional statements whose Boolean conditions are enabled or disabled by the Administration command :EXM. Once enabled, the code creates timing point information consisting of varying numbers and types of properties, totaling 92 characters.
Once built, the timing points are passed to the collection library to be blocked and later stored on disk.
You can enable or disable timing points by entering Administration (colon) commands from the application, or as Accepts to the LSS program. If you enter them from the application, they are only accepted if you have a Controller station with an ODT access level of 2.
The Administration command variants are:
:EXM+ [pack]
Use this command to start timing. It sets a flag in COMSTP, GLI, Offline, and LSS, to call Examiner timing points in the Examiner Library.
If the Examiner Library is not initialized (not currently running), a file under the usercode of the application initializing it is opened. If a pack is specified, the file is located on that pack. If no pack is specified, it goes to the pack on which the Examiner/Library is located.
If a file is already open, the command only sets the flag to enable Examiner timing points in the application.
:EXM-
Use this command to turn off the Examiner flags in your application.
:REL EXM [pack]
Use this command to release the Examiner file, and to optionally open another file on the specified pack.
The properties common to all timing points are:
Unique Identifier. The Examiner Unique Number and Key used to identify individual transactions.
Record Code. The tag used to identify the type of timing point.
Code Identifier. The tag used to subdivide record codes.
Timestamp. The time where the timing point was taken.
Mix Number. The mix number of the program.
The properties specific to various timing points are:
Ispec: transaction type
Pivot: Pointer to transaction within LINCLOG
CPU: Processor time for the transaction
Subsystem: Subsystem number
System Name: System name
Finds: Number of DMS II Finds
Stores: Number of DMS II Stores
Message Size: Length of transaction in characters
Glb.ExamKey: User-defined, thirty character (five-word) storage area
Refer to Transaction Flow Diagrams for more information on transaction flow diagrams. Refer to Record Layouts for more information on record layouts for each timing point.