WebAS ABAP Performance Monitoring

RESPONSE TIME = roll in + wait + load/gen + database + processing + roll wait + enque + etc 

 a. Wait time = queue time to wait for free work process (DIA) in SM50. Should be < 50ms, else it is an indication of not enough DIA wp in SM50 or all DIA tied to long running programs. Ensure the extended memory full is sufficient before adding more WPs.

b. Roll in/out time = time copy user context to/from (information related to a transaction like internal table, parameters, screen list) the work process memory. Should be <20ms, else tuning the roll memory and extended memory.

c. Load time = time to load and generate program and screens from the SAP buffers. Should be <50s, else is an indication of too small SAP program buffer.

d. Database time = Time to read or insert to the database. DB time should be <40% of total response time. High DB time indicates incorrectly tuned database, I/O disk problems in db or most likely slow/expensive SQL statements. If it is caused by customized report, you should optimize the ABAP codes (ST05 to execute ABAP SQL trace).

e. Processing time. If processing >>> 2x CPU time, is an indication of CPU bottleneck.
CPU time is not part of total response time !

f. Roll wait time = time to wait for reply from RFC connections. Roll wait time is more or less equals to GUI time, as SAPgui is considered an RFC from SAP apps server point of view. Roll wait time > 200s indicates slow network or PC.

g. GUI time = time used for data transfer from SAP server to SAPgui workstation. It includes the time in the LAN/WAN. There could be several roundtrips to complete for transaction. Long GUI time can indicate network performance (WAN/VPN) or slow processing PC. I’m still trying to get a good definition of the diff between GUI time ang Network FE time.

h. Enqueue time = time for wp to set an enque (lock row). Should be minimal.

~ by onnry on July 5, 2008.