Symptom
Analysis Studio performance is slower then what was seen in PPWeb. What took 8 seconds in PPWeb is taking 20 seconds in Analysis Studio.
Cause
Analysis Studio and PPWeb are two different products built from different architecture, just as product features, performance cannot be compared between the two. That being said however there are techniques that can be used to speed up the display of OLAP reports in Analysis studio. These techniques are below.
Solution
There are four things that will help with Analysis Studio Performance.
-fixed column widths
-crosstab caching (transformer)
-sort memory, read cache
-rows per page
A test was done in PPWeb that took 8 seconds. Those same 5 steps took 20 seconds in Analysis Studio.
After modifying each of the settings above Analysis Studio was able to perform the five steps in 11 seconds.
fixed column widths
Note: The FixedColumnWidth property applies to Cognos 8.1 only.
In the ansproperties.xml file find and uncomment the following section and change the value from 0 to 1.
<!-- crosstab performance tunning: when this property is turned on, client will rendering crosstab columns based on fixed width -->
<property>FixedColumnWidth</property>
<value type="long">1</value>
Once this is done, labels that exceed the fixed width will be truncated, ellipses will show up. Hover over the truncated cells, you'll see a tool tip with the full information. Also, hover over the vertical border between two columns, you'll see a "resize" styled cursor.
Crosstab caching
If you enable crosstab caching on your cube in Transformer prior to it being built you will also see an improvement in performance.
This option speeds up cube access in PowerPlay by storing summaries for the initial PowerPlay crosstab in the cube. It slightly increases the cube size and so does not speed up cube creation times in Transformer. However, it does speed up the default report display time in PowerPlay.
Sort Memory/Read Cache
As with PPWeb viewing the contents of the cube will be quicker if you adjust the read and sort memory. In Cognos8 Sort Memory is found in Cognos Configuration under Environment. Read Cache is found in configuration/ppds_cfg.xml file.
Rows per Page
This is where you may see the most gain. In Analysis Studio there are many more underlying components of each cell which causes rendering time to cost more then PPWeb. To cut down on the time taken to return the report in AS reduce the rows per page from the default of 200 to something more manageable such as 25 - 50
Rows per page is found in the ansproperties.xml file (within the configuration folder). Remember to rename the file from ansproperties.xml.sample to ansproperties.xml once it is modified.