Hi Joie,

Thanks for your suggestion. You are pretty much correct. I figured out the problem to be related to the parameter.

The table has over 40 million rows and one of the columns that I'm filtering using a parameter, I created a dataset for it. Initially, the dataset was used to generate a drop down list value for that parameter, but that took too long and I decided to set the Available Value parameter property to none since I was passing the value to the parameter from the primary report.

What I didn't realize is that even though I wasn't using that dataset for the parameter, because there was a query associated with the dataset, SSRS must still run that query and load it into memory. Once I deleted that dataset, it rendered results much faster than before.

The one thing that I haven't tested was setting up a SP to run the query and just call that. Thanks to your suggestion, I will give that a try for future scenarios using large datasets. I keep forgetting that SP's are supposed to improve overall performance anyway.

Thanks for your reply!!