Currently we are using SQL Server 2005 in Production and we also have testing server with SQL Server 2008 R2. and there are same set of reports in both the servers. Now the problem I am seeing is that some of the complex reports are running slow in 2008 R2 server. And the main difference is in Processing time (TimeProcessing column from ExecutionLog table). One report I am running has one dataset and the query is returning around 86K rows and report has 9 matrix (in which I have Sum aggregation) and a chart. 2005 Server : TimeDataRetrieval : 6 sec , TimeProcessing : 51 sec, TimeRendering : 0 sec 2008 R2 Server: TimeDataRetrieval : 13 sec , TimeProcessing : 234 sec, TimeRendering : 0 sec Note: Index structure is not same in both servers, that's why there is a difference in Data Retrieval. I am not worrying about that for now. Here are the server comparison. 2005 Server: Quad-Core AMD Opteron Memory: 16 GB OS: Windows Server 2008 2008 R2 Server: Quad-Core AMD Opteron Memory: 32 GB OS: Windows Server 2008 R2 Size of the ReportServerTempDB is almost same ~ 600 MB in both of them and both servers are used for Reporting only. So my question is what am I missing here? Why is the huge difference in Processing? I know I can do all the aggregation in sql side and reduce the number of rows. My only concern is the difference in processing time by two servers for the same report.

Hi I also am seeing some differences in speed in SSRS 2005 reports published to SSRS 2008 R2, Are you able to open a copy of the 2005 reports into BIDS 2008 R2 set the published server type to your 2008 R2 My limited test seems to indicate SSRS 2005 reports take longer to process because they run in compaitiblity mode not native 2008 R2 mode If you get some figures i would be interested in resultsHope this helps Robert Edgson

Hi Robert, I have migrated the complete project with all the reports from 2005 to 2008 R2. So now I have two separate copies of project, 2005 and 2008 R2 on different servers. In 2008 R2 version of project, In Proejct Preperty-->Deployment --> TargetServerVerison is set to 2008 R2. Is that what you meant when you said "run in compaitiblity mode not native 2008 R2 mode" ....or somewhere else?

Hi , I was more wondering if the ssrs 2005 report was directly published to your 2008 r2 server. Because this adds extra processing time to the report. sadly this means your observations are different to mine. FYi ExecutionLog2.AdditionalInfo ProcessingEngine Identifies the version of the processing engine utilized for the report. 1 = Yukon Engine 2 = On-Demand Processing Engine After a deployment is upgraded to RS 2008, reports will internally auto-upgrade to the latest RDL 2008 schema so that the on-demand processing engine can be used for processing. However, if the auto-upgrade is not possible (e.g. reports that were built with 2005-based CustomReportItem controls), those particular reports will be processed with the old Yukon engine in a transparent backwards-compatibility mode. from this blog http://blogs.msdn.com/robertbruckner/archive/2009/01/05/executionlog2-view.aspx If this is not your issue and you can replicate the issue I suspect you wil get a better response in the SSRS R2 forum http://social.msdn.microsoft.com/Forums/en-GB/sqlkjreportingservices/threads Hope this helps Robert Edgson

Hi, No It wasn't directly published to 2008 r2 server. I've looked into Executionlog2.AdditionalInfo and all the reports are using ProcessingEngine = 2. i.e. On-Demand. As you have suggested, I'm asking the same question in SSRS R2 forum. Thanks.

Malcom Stewart's reply to the question.. http://social.msdn.microsoft.com/Forums/en-GB/sqlkjreportingservices/thread/db837806-eed7-403d-9329-de2ab2c7696a

Hi, Why can we not see "Malcom Stewart's reply to the question.." http://social.msdn.microsoft.com/Forums/en-GB/sqlkjreportingservices/thread/db837806-eed7-403d-9329-de2ab2c7696a Why are we; "You are not authorized to perform this action." I would like to see his comments and answers please? Regards AlexAlex Young