Universal Messaging 10.3 | Developer Guide | Enterprise APIs | Enterprise Developer's Guide for VBA | Publish / Subscribe | Learn More | Setting the RTD Throttle Interval
Setting the RTD Throttle Interval
Excel Throttle Interval
When Microsoft Excel receives a notification that new data is available it will only respond if it is not busy* and if the throttle interval has passed. By default Excel sets a throttle interval of 2 seconds which means that updates cannot be received faster than every 2 seconds. A high throttle value does not mean that events will be missed. The Universal Messaging RTD server queues events and will process the entire queue internally before returning data to Excel.
*Excel is said to be busy whenever it is recalculating but also when the user responds to dialog prompts or enters data into a cell.
Changing the Excel Throttle Interval
The throttle interval is stored in the Windows registry but you may wish to set a different throttle interval for different spreadsheets. In order to do this you need to use VBA.
*Open Excel and switch to the VBA window
*In the Project Explorer panel double click on "ThisWorkbook"
*This will bring up a new code window. In this window enter the following code

Private Sub Workbook_Open()
Application.RTD.ThrottleInterval = 0
End Sub
By setting a throttle interval of 0, Excel will try to respond to update notifications whenever it is not busy. A value of -1 will set the RTD server to manual mode which means Excel will not respond to any update notifications. Instead the user must manually call the RTD server to request new data.