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Issue: Data Tables may become really slow to load, and this is due to SmartGWT's processing of the grouping levels (well noticeable from 5 to 8 levels). (SmartGWT is a 3rd party underlying UI framework.) It is quite common to experience loading 4000+ rows for about one minute on a fast machine (i7 quad with 16GB of RAM) in any browser. 

Resolution: See 1159462922 How to Deal with Analytics Data Table's UI Responsiveness? below. 

Unresponsive Application in Firefox

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Issue: Once a Data Table has been displayed, the UI may become less responsive – even after switching to a different PFX tab. This behavior was observed on Mac with Chrome and Safari; presumably Chrome on Windows will perform similarly. It happens when 1000+ rows are displayed, either when the table is totally ungrouped, or when it is grouped with most or all of its nodes expanded.

Resolution: See 1159462922 How to Deal with Analytics Data Table's UI Responsiveness? below. 

Conclusions

To deal with the issues above, try the following:

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