topic Re: regarding performance issue in Application Development and Automation Discussions

regarding performance issue

Former Member — Fri, 08 Jun 2007 09:35:34 GMT

hi experts

suppose one program performance will take 12 hour,regarding performance tunning technique used i minimised 12 hr to 8 hr.

the main question is again what r the methods/performance that we have to use

that decreases 8 hr to 2 hr.i faced recently this question from ibm.

thanks

subhasis

Re: regarding performance issue

Former Member — Fri, 08 Jun 2007 10:57:48 GMT

1) Dont fire select query on same DB more than one time.

2) Check if itab is not initial when using FOR ALL ENTRIES.

3) Avoid two if condition for the radiobuttons having common radiobutton group like LIST & FORM in this case.

4) before creating field ALV stuff check output itab is not inital.

1. Before selecting sort the internal tables by the key fields.

2. Might be the internal table data is more use BINARY SEARCH when reading a table with key.

3. Use workareas instead getting data into internal table header.

4. For MODIFY statement give the row no. to modify with the values.

e.g: INDEX row_no TRANSPORTING FROM wa.

5. Clear fields, workareas whenever there is no use. FREE the tables which u don't require for further processing.

6. Give as many conditions while selecting data from database tables in WHERE conditions.

7. Don't use System variables directly like SY-INDEX while modifying or any process instead assign this value to ur local variable and use it.

8. Before selecting data from database tables using FOR ALL ENTRIES OF TABLE itab check whether the internal table u r using contains any data.

9. Instead of MOVE-CORRESPONDING assign the values directly to the fields of internal table and append

Regards

suresh.D

Re: regarding performance issue

Former Member — Mon, 11 Jun 2007 06:16:29 GMT

hi,

first we have to minimise code redundency.

->avoid inner joins and use FOR ALL ENTRIES.

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

->if u are using Database frequently i.e if u want to retrive the data more than one time from the same table depending on conditionthen first write one select statement using all the conditions and store the data into internal table.

make use of READ statement to retrieve data from that internal table ,this will decrese the database utilization.

->avoid nested looping.

-> if u want o get data depending on checking radio boxes etc,selec the data depending n the condition.i.e

for example if u want to display vendor information when ven check box is clicked,display customer information when cust check box is clicked,instead of retrieving data from all the relavent tables write coding

if ven = 'X'.

write select statement to retrive vendor data.

elseifcust = 'X'.

write select statement to retrive customer data.

endif.

this will decrese performance very well.

->make sure u dont have any unused variable declarations etc.

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