Abnormal system situation
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
Exclusive lock waits/locking situations (2000000 locks available)
Data received/asked from user when they report an issue
What runtimes are you seeing?
What runtimes do you usually have/need?
Time of day
Anything else they can tell us for context
What changed (code, customizing, business process)?
/SE38 (in DEV)
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.
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:
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.
/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
/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.