I was discussing with a Customer recently  some recommended best practices for controlling the size of the Sysvol Folder. As you are probably aware, the Sysvol folder is the location where all of your Group Policy Template files, Settings and Scripts are stored. The File Replication Service is responsible for replicating this to other DC's within the domain. However the key difference between this and Active Directory Replication is that if you change 1 byte on the Sysvol folder this will initiate replication of the whole folder. Therefore one for the best recommendations to our customers is to remove the .ADM templates from being stored in with the Group Policy Template files. By enabling the following  Group Policy Settings as shown below;

 

 

This will ensure your Adm templates are no longer stored  on your Sysvol Folder and will significantly reduced the size of the Sysvol folder, and hopefully reduce unnecessary policy-related replication traffic.

 So in summary the steps to reduce the size of your Sysvol is as follows;

1.Enable the " Turn off automatic update of ADM files? policy setting for all Group Policy administrators who will be editing GPO?s. (As shown above)

2. Make sure that this policy has been applied. (Gpupdate /force)

3. Copy any custom ADM templates to the %windir%\Inf folder.

4. Edit existing GPO's, and then remove all ADM files from the GPT. To do this, right-click Administrative Templates, and then click Add/Remove Template.

5. Enable the "Always use local ADM files for Group Policy Object Edit" policy setting for administrative workstations.