Had an interesting issue today where the C drive for a developers SQL instance had run out of space, doing a quick look for big files we found a 24GB file in the SQL Server Agents Service accounts User profile, example below:

C:\Users\<SQLSERVERAGENTSERVICEACCOUNT>\AppData\Local\Temp\<SERVERNAME + INSTANCE>_{49268954-4FD4-4EB6-AA04-CD59D9BB5714}_4.cache”

The folder was full of these files, (though most of them were much smaller). These are created by MDW which stores a cache of its data by “default” in the Temp folder of the Account running the collection (C:\Users\<Username>\AppData\Local\Temp). You make this choice when you configure the clients to use MDW see the picture below:


Someone had turned off the MDW warehouse and missed disabling one of the clients. As the MDW was no longer needed I just deleted the files and the server was back up and happy, I believe if you turned back on the MDW Warehouse it would start loading those cache files in and gradually remove them as well. Its certainly good to know that if you lose connection to the MDW warehouse you don’t get flooded with errors or warnings. but definitely one to keep an eye out on.