The DSCACHE files are temporary files used during the sync process, they contain a copy of the Data Source Data and can be safely deleted.
The files are automatically deleted during the .NET Garbage Collection however sometimes they are left behind using up disk space.
DSCACHE File Location
If you want to move the file location that Data Sync uses to store it’s temporary cache files during the data load and compare you should create a System Environment variable called DATASYNCCACHEPATH that points to the new file location.
The folder must exist and it should not be a network share.