This statement enables the user to start automatic analysis of bottlenecks for the selected time interval (see "Automatic performance analysis"). For a complete analysis, monitored data from the monitoring programs SERVICETIME, SYSTEM, TASK and (if available) VM must be additionally available for the relevant analysis period. SM2R1 outputs the results of the analysis to the selected output medium.
Format
START-AUTOMATIC-ANALYSIS |
MAIN-APPLICATION = *TP / *DIALOG / *BATCH ,OUTPUT-MEDIUM = *BOTH / *SYSLST ,IMPORTANT-CATEGORIES = *STD / list-poss(16): <alphanum-name 1..7> |
Operands
MAIN-APPLICATION = *TP / *DIALOG / *BATCH
Specifies the main application mode of the system: transaction processing (TP), dialog mode (DIALOG) or batch processing (BATCH).
OUTPUT-MEDIUM = *BOTH / *SYSLST
Specifies the output medium SYSLST or the system files SYSLST and SYSOUT (*BOTH).
IMPORTANT-CATEGORIES =
Specifies the names of the important categories.
IMPORTANT-CATEGORIES = *STD
The SM2R1 program selects the important categories itself. The criterion for the importance of a category is its weight. The third of all categories with the greatest weight are selected.
IMPORTANT-CATEGORIES = list-poss(16): <alphanum-name 1..7>
Lists the names of the important categories.
If there are no important categories, the following is output:
IMPORTANT CATEGORIES:
*NONE
This happens when the corresponding record does not exist or the user specifies categories that do not exist in the output file.
Example
//START-AUTOMATIC-ANALYSIS MAIN-APPLICATION=*DIALOG
This statement starts automatic analysis for a system with dialog mode as the main application.
Conventions and results
For the basic principles behind automatic performance analysis, refer to the “Performance Handbook” [5].
The rules governing the detection of resource bottlenecks can be subdivided into the groups CPU, IO, Paging and VM2000.
Example
START OF AUTOMATIC ANALYSIS
MAIN APPLICATION: TP
IMPORTANT CATEGORIES:
BATCHDB
TP
DIALOG2
!!! PARAMS UNBALANCED CATEGORY,
- CATEGORY TP WAITS FOR CPU LONGER THAN CATEGORY ...
- PRIORITIES ARE NOT BALANCED.
- RAISE PRIORITY FOR CATEGORY.
!!! CPU BOTTLENECK, TP
- WAIT TIME FOR CPU EXCEEDS RECOMMENDED LIMIT FOR CATEGORY TP
- TOO HEAVY CPU USAGE OF CATEGORY. SYSTEM PARAMETERS ARE BALANCED.
- INCREASE CPU SPEED.
!!! PUBLIC DISK OVER UTILIZED, (A832,20S7.2)
- UTILIZATION OF PUBLIC DEVICE (A832,20S7.2) EXCEEDS RECOMMENDED LIMIT.
- TOO MANY USERS FOR SAME DISK.
- TAKE CARE FOR UNIFORM UTILIZATION OF PUBLIC VOLUME SET.
END OF AUTOMATIC ANALYSIS
For each bottleneck diagnosed, three records are output to SYSLST and optionally output to SYSOUT:
Record 1 includes the description of the bottleneck, record 2 lists the possible reasons, while record 3 gives instructions on how to tune the system.
In addition, it should be noted that the SM2 values are checked against other configuration specific performance data, having previously determined the SM2 values for the set time period. For this reason automatic analysis is not performed over the entire time period specified, otherwise the probability of any peak times being corrupted by any underload times would be too great; rather, automatic analysis is only performed for time periods which have already been recognized as being of critical importance.
If no potential bottleneck is indicated, this does not imply that no bottleneck actually exists, rather it merely indicates that SM2R1 was not able to identify any bottleneck using the resources available to it. If the system response nevertheless remains unacceptable, a systems analyst or technician must be called in to analyze system performances. Nevertheless, the SM2 system does allow the user to avoid needless routine and drudgery.