Jet Reports – Slow when generating reports over Terminal Services

I was recently flown down to Canberra to investigate a finance system which was running NAV 2009 and JET v7 reporting over terminal services (remote desktop). The company was reporting poor performance issues when generating JET reports.

First thing I looked at was the hardware resources thrown at the system. I ran a bunch of reports and monitored the hardware to see if there were any bottlenecks on both the terminal services server and the NAV SQL server which hosts the database the JET report plugin queries. I couldn’t seem to find anything here. The server was running at half capacity, yet I knew that there had to be a performance issue.

I then tried logging onto the TS server with a new remote desktop connection. This is where I got lucky and stumbled upon the solution. I connected without adding local printer mapping in the remote desktop client and tried the same report I was testing. I found that the report went from taking 5 minutes and 9 seconds to taking just a little over 20 seconds. Further tests with larger reports provided better outcomes with reports which took 4 hours now only taking 20 minutes.

After investigating I found that the issue lies within Excel and its default behaviour to check with the printer for page dimensions during each cell repopulation while generating a JET report. The huge delays will arise if your default printer at the time of generating a JET report is at a remote location to the TS server (remote back and forth communication takes some time between excel and the remote printer). The simple workaround is to disable the group policy which enables the default printer as the default client printer and make it something like a PDF creator on the TS server (a local printer to the TS server) which means fast reporting with the functionality to still print when required. So you can still map your local printers but now it won’t be the default printer and you will have to select your printer from the print prompt printer list. It’s a small price to pay for much faster JET reporting.

I hope this helps!