Any ideas on why the SSRS report would run so slow in this particular environment?
I have an SSRS report that calls out to a stored procedure. If I run the stored procedure directly from a query window, it will return in under 2 seconds. However, the same query run from an 2005 SSRS report takes up to 5 minutes to complete. This is not just happening on the first run, it happens every time. Additionally, I don't see this same problem in other environments.
It sounds like a possible bad parameter sniffing situation. Different parameter values on different systems with different sets of statistics will lead to variable performance on some queries. I would check that the statistics are up to date on all the servers, first. If necessary, update them with a full scan. If that doesn't resolve the issue, compare the execution plans to understand what is occurring on each server. If the data sets between servers are different, that might be the answer right there.