This is a work-around to this Idea: http://community.tableau.com/ideas/2657
This allows the Tableau administrator to kill a Background Task on the Tableau Server by ending the associated process in the Windows Task Manager. This comes in particularly useful if an extract needs to be stopped without having to restart the Server
1. From the Server Status page hover your mouse over the running backgrounder.
2. Get the last four digits that display in the tooltip. In the below example it's 8253:
3. Now open the Windows Task Manager.
4. Click on the Processes tab.
If you don't have the Command Line column visible then display it. Here's how:
4a. Click on View >> Select Columns...
4b. Select the Command Line box then click the OK button:
4c. You'll now have the Command Line column and you can drag it where you want:
5. Sort the image name (click on the column header to toggle the sorting of the column).
6. Expand the Command Line column and go to the end of it for the "backgrounder.exe" image names:
The number that is in the red box above is the port number. It is the first port number you will see (-Dcom.sun.management.jmxremote.port=) in the Command Line. I have four backgrounders so their backgrounder ports are 8550, 8551, 8552, & 8553.
7. From step #2 the Backgrounder value was "8253" so from the above image I selected the second task in the Task Manager (the blue row already highlighted) because the Command Line has "53" as the last two digits in the port number in that piece of the command. So we are not concerned about the first two digits, only the last two digits we look at.
8. Right-click on the highlighted row and select End Process OR click on the End Process button:
8a. If prompted, confirm that you do want to end the process.
9. Windows will kill the process and it will disappear. In a couple seconds Tableau will look annoyingly at you and restart the process. This is perfectly normal and expected.
10. Typically in a few seconds the Tableau Background Task will be killed:
I've notice that sometimes this can take up to a minute to register in the viz; just keep clicking the Refresh every few 5-10 seconds and it will change from In Progress to Error. Tableau does a good job at cleaning up the process to avoid memory leaks.
For earlier versions of Tableau Server (e.g. 8.x) please see Stopping a 8.x Tableau Server Background Task (Windows)