Acute Problems
Abnormal system situation
Specific problem
CPU on the Apps server (poor ABAP)
Database (everything on USUNX07
This data can be reviewed by using /STAT
Main problems lay in:
Expensive SQL, indexes
IO Bottlenecks
Exclusive lock waits/locking situations (2000000 locks available)
Qualitative Data
Data received/asked from user when they report an issue
What runtimes are you seeing?
What runtimes do you usually have/need?
Which server?
Selection criteria/circumstances
Time of day
Anything else they can tell us for context
Quantitative Data
What changed (code, customizing, business process)?
/SE38 (in DEV)
ABAP editor
In program attributes you can then see who touched the program last (developer)
In Utils, Version Management you can see when the last version was transported.
Locks
There are 2 types of locks:
Database locks. Maintained by IDS for database integrity.
Enqueue locks. Arbitrated by SAP to maintain application integrity (follows business logic). Enqueue locks should be released by killing the user session from /SM04.
/SM12: Enqueue Lock entries. Blue are updates, black are user busy.
Locks can cause the following problems:
Performance
Deadlocks. Because a process won’t release it’s current lock until it gets it’s new lock, deadlocks can occur. Deadlocks occur when:
Process A wants a lock on field 1 while it has a lock on field 2.
Process B has a lock on field 2 and wants a lock on field 1.
Both processes won’t give up their lock until they have the new lock. Eventually SAP will kill of one of the processes so the system can run on.
Expensive SQL
/ST05: SQL Trace. Traces everything the ABAP processor does on a specified server. This has the option to Explain SQL. The Estimated Cost (derived by the Informix optimizer) shows how “heavy” the SQL is. A cost > 1000 is bad.
/ST04: database analysis. The detail analysis shows lots of useful data for the database
Transaction overview
/SE11 – Database Dictionary
/SE16 – Data browser. Will show how big a table is
/ST04 – Can also be used to calculate the cost of SQL for running processes. In Detail Analysis, go to Informix Session.