Hi Suresh,
This is an older post but I am replying just in case you are still having this issue.
The problem is likely related to a known issue that was in earlier versions of the BI 4.0 release. There was an issue where the Connection Server was making a lot of redundant calls to the CMS trying to update its health status. Fixed versions and more details on this issue can be found in the following KBA:
1846212 - Web Intelligence reports that use UNV connections to 32-bit data sources are slow to refresh
Another thing you may want to keep in mind is that newer versions of BI 4.0 and BI 4.1 ship a 64-bit RFC driver for Windows which allows the older UNV universes to be processed with the 64-bit Webi Processing Server. This can improve performance and stability.
Thanks,
Jonathan