Performance Tuning - Suggestions

[Former Member]

Hi,

I have an ABAP (Interactive List) Program times out in PRD very often. The ABAP run time is about 99%. The DB time is less than 1%. All the select statements has the table index in place. Actually it isprocessing all the Production Orders (Released but not Confirmed/Closed). Please let me know if you have any suggestion.

Appreciate Your Help.

Thanks,

Kannan.

[rodrigo_paisante3]

Hi,

Please, post partial or full code here, than the experts can advise your beter.

Regards

RP

[Former Member]

Hi

1) Dont use nested select statements

2) If possible use for all entries in addition

3) In the where addition make sure you give all the primary key

4) Use Index for the selection criteria.

5) You can also use inner joins

6) You can try to put the data from the first select statement into an Itab and then in order to select the data from the second table use for all entries in.

7) Use the runtime analysis SE30 and SQL Trace (ST05) to identify the performance and also to identify where the load is heavy, so that you can change the code accordingly

https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/5d0db4c9-0e01-0010-b68f-9b1...

ABAP performance depends upon various factors and in devicded in three parts:

1. Database

2. ABAP

3. System

Run Any program using SE30 (performance analys) to improve performance refer to tips and trics section of SE30, Always remember that ABAP perfirmance is improved when there is least load on Database.

u can get an interactive grap in SE30 regarding this with a file.

also if u find runtime of parts of codes then use :

Switch on RTA Dynamically within ABAP Code

*To turn runtim analysis on within ABAP code insert the following code

SET RUN TIME ANALYZER ON.

*To turn runtim analysis off within ABAP code insert the following code

SET RUN TIME ANALYZER OFF.

Always check the driver internal tables is not empty, while using FOR ALL ENTRIES

Avoid for all entries in JOINS

Try to avoid joins and use FOR ALL ENTRIES.

Try to restrict the joins to 1 level only ie only for tables

Avoid using Select *.

Avoid having multiple Selects from the same table in the same object.

Try to minimize the number of variables to save memory.

The sequence of fields in 'where clause' must be as per primary/secondary index ( if any)

Avoid creation of index as far as possible

Avoid operators like <>, > , < & like % in where clause conditions

Avoid select/select single statements in loops.

Try to use 'binary search' in READ internal table. Ensure table is sorted before using BINARY SEARCH.

Avoid using aggregate functions (SUM, MAX etc) in selects ( GROUP BY , HAVING,)

Avoid using ORDER BY in selects

Avoid Nested Selects

Avoid Nested Loops of Internal Tables

Try to use FIELD SYMBOLS.

Try to avoid into Corresponding Fields of

Avoid using Select Distinct, Use DELETE ADJACENT

Check the following Links

http://www.sapgenie.com/abap/performance.htm

http://www.thespot4sap.com/Articles/SAPABAPPerformanceTuning_PerformanceAnalysisTools.asp

check the below link

http://www.sap-img.com/abap/performance-tuning-for-data-selection-statement.htm

See the following link if it's any help:

http://www.thespot4sap.com/Articles/SAPABAPPerformanceTuning_PerformanceAnalysisTools.asp

Check also http://service.sap.com/performance

and

books like

http://www.sap-press.com/product.cfm?account=&product=H951

http://www.sap-press.com/product.cfm?account=&product=H973

http://www.sap-img.com/abap/more-than-100-abap-interview-faqs.htm

http://www.thespot4sap.com/Articles/SAPABAPPerformanceTuning_PerformanceAnalysisTools.asp

Performance tuning for Data Selection Statement

http://www.sap-img.com/abap/performance-tuning-for-data-selection-statement.htm

Debugger

http://help.sap.com/saphelp_47x200/helpdata/en/c6/617ca9e68c11d2b2ab080009b43351/content.htm

http://www.cba.nau.edu/haney-j/CIS497/Assignments/Debugging.doc

http://help.sap.com/saphelp_erp2005/helpdata/en/b3/d322540c3beb4ba53795784eebb680/frameset.htm

Run Time Analyser

http://help.sap.com/saphelp_47x200/helpdata/en/c6/617cafe68c11d2b2ab080009b43351/content.htm

SQL trace

http://help.sap.com/saphelp_47x200/helpdata/en/d1/801f7c454211d189710000e8322d00/content.htm

CATT - Computer Aided Testing Too

http://help.sap.com/saphelp_47x200/helpdata/en/b3/410b37233f7c6fe10000009b38f936/frameset.htm

Test Workbench

http://help.sap.com/saphelp_47x200/helpdata/en/a8/157235d0fa8742e10000009b38f889/frameset.htm

Coverage Analyser

http://help.sap.com/saphelp_47x200/helpdata/en/c7/af9a79061a11d4b3d4080009b43351/content.htm

Runtime Monitor

http://help.sap.com/saphelp_47x200/helpdata/en/b5/fa121cc15911d5993d00508b6b8b11/content.htm

Memory Inspector

http://help.sap.com/saphelp_47x200/helpdata/en/a2/e5fc84cc87964cb2c29f584152d74e/content.htm

ECATT - Extended Computer Aided testing tool.

http://help.sap.com/saphelp_47x200/helpdata/en/20/e81c3b84e65e7be10000000a11402f/frameset.htm

Just refer to these links...

You can go to the transaction SE30 to have the runtime analysis of your program.Also try the transaction SCI , which is SAP Code Inspector.

1 Always check the driver internal tables is not empty, while using FOR ALL ENTRIES

2 Avoid for all entries in JOINS

3 Try to avoid joins and use FOR ALL ENTRIES.

4 Try to restrict the joins to 1 level only ie only for 2 tables

5 Avoid using Select *.

6 Avoid having multiple Selects from the same table in the same object.

7 Try to minimize the number of variables to save memory.

8 The sequence of fields in 'where clause' must be as per primary/secondary index ( if any)

9 Avoid creation of index as far as possible

10 Avoid operators like <>, > , < & like % in where clause conditions

11 Avoid select/select single statements in loops.

12 Try to use 'binary search' in READ internal table. Ensure table is sorted before using BINARY SEARCH.

13 Avoid using aggregate functions (SUM, MAX etc) in selects ( GROUP BY , HAVING,)

14 Avoid using ORDER BY in selects

15 Avoid Nested Selects

16 Avoid Nested Loops of Internal Tables

17 Try to use FIELD SYMBOLS.

18 Try to avoid into Corresponding Fields of

19 Avoid using Select Distinct, Use DELETE ADJACENT.

Regards

Anji

[Former Member]

It's probably nested loops. Check:

<a href="/people/rob.burbank/blog/2006/02/07/performance-of-nested-loops">Performance of Nested Loops</a>

Rob

[Former Member]

Run SCII on the program and do all the performance checks. To do this, expand the Performance Checks item in the list and click the check box twice. All of the sub-items for performance should be selected.

The following are the items that it checks:

<i><b>Performance Checks</b>

Analysis of WHERE Condition for SELECT

Analysis of WHERE Condition in UPDATE and DELETE

SELECT Statements That Bypass the Table Buffer

SELECT Statements with Subsequent CHECK

SELECTs in Loops

Changing Database Accesses in Loops

Nested Loops

Low Performance Operations on Internal Tables

Low-Perform. Parameter Transfers

Copy current table row for LOOP AT ...

EXIT or no statement in SELECT...ENDSELECT loop

Invalidation of SAP Table Buffer

Instance Creation of a BAdI: Missing Import Parameter

Table Attributes Check</i>

You will probably also want to click the arrow for "Low Performance Operations on Internal Tables" and check the entry for STANDARD TABLES.

This is because one other common cause of slow processing in a scenario like yours, where the database time is minimal, is poor handling of internal tables.

Rob pointed out the nested loop issue, but this can be compounded with bad design with regard to READ on tables, if the READ forces sequential access.

You can fix this problem by either sorting the tables and using BINARY SEARCH on the READ, or (if the tables have UNIQUE keys) you can used HASHED tables.

Good luck

Brian

PS

You can also use SCII for other type of checks. It is a valuable tool.