BPS read performance

[Former Member]

Hello colleagues!

I have some questions on performance issues

1.Can anyone explain why BPS is readinf data from infocube using sequentional, rather then direct read?all indices and statistic is up-to-date (picture frjm sm50)

4 DIA 9651 Running Yes SAPLRSDRS 400 JDOE Sequential read /BIC/FTEST

2. we have mulltiplanning area and copy data from A1 to A2

BPS reads data from A2 twice (we can see that in BPS_STAT0). First time - with "E" mode(exclusive lock), second - as ref data. But we don't use A2 area in right part of experssions! Single read is enough from our point of view. What should we do to exclude second reading?

BW 3.0B SP21, SEM 3.1B SP28

Best regards

Alex

[former_member93896 · Accepted solution]

Hello Alex,

you didn't say which database the system is running on...

1) Assuming it's Oracle, the DB indexes are different on the F-table. Never the less, BW adds the STAR TRANSFORMATION and FACT hints to the SQL so Oracle should do a star join. If not, check if you have the latest Oracle patches. If yes, open a customer message so Oracle CoE can check it.

2) If this is a standard copy function and the planning packages contains only A1 data, then there should be only one read on A2. I guess you are using a FOX formula. If you set a local variable for a characteristic using TMVL, ATRV, or ATRVT and use this variable in a reference data operand (right side of formula), then the system ignores any restrictions for this characteristic when reading the reference data form the database. This can lead to major performance problems! Check the BPS statistics for very long database selection for reference data. Check that SAP note 729362 is implemented (or BW 3.5 SP 2). However, there's no easy workaround.

Regards,

Marc

SAP NetWeaver RIG

[Former Member · Accepted solution]

Marc,

regarding topic 2 - we had traced how BPS selects reference data and found, that sometimes it unreasonably extends reference data, particularly when using TMVL(as you mentioned) and in some other cases.

Existing notes (below) doesn't help

But we now learn how to analyze generated ABAP code and we can extend result data selection to meet reference data selection and thus exclude double reading. Regrettably, it's not applicable in all cases

729362 - Planning function type formulas: Reference data

529470 Planning functions: Function VARV reads too many values

547809 Planning functions: Function TMVL changes value of arguments

610430 Planning functions: Not enough reference data read

646618 Planning function: FOREACH using reference data

703966 Planning functions: Type of formula ELSEIF - statements

Best Regards

Alex