The Plex Media Server data directory contains nearly all the information about your server installation. This includes the database file with your library information as well as metadata, artwork, caches, and more.
Related Page: Where is the Plex Media Server data directory located?
What’s Taking Up Space?
In a standard Plex Media Server installation, the majority of space here will be taken up by metadata—particularly by artwork. These are found under the Metadata and Media subdirectories. It isn’t uncommon for installs to take several gigabytes of space. If you make use of Mobile Sync, it’s also possible for sync files to take up a significant amount of space.
Video Preview Thumbnails
One of the most common reasons for unexpectedly-large data directories is when people have enabled video preview thumbnails generation. If you’ve enabled that for your content, it can consume significant amounts of space. Installations with a large number of media items in your library can easily take dozens or even hundreds of gigabytes of space when generation of video preview thumbnails is enabled.
Related Page: Video Preview Thumbnails
Sync Jobs
When you set up a sync job for Mobile Sync, your Plex Media Server will process the files before they’re ready to sync. If you create a really large sync job (say, an entire season or series of a television show or a large number of movies), those will all need to be prepared before they’re ready to sync. That means they may be taking up a large amount of disk space until the sync completes.
Tip!: This also applies if you enable the Allow Sync option when sharing with other users. If a shared user creates a large sync job, it will affect your server.
Related Page: Downloads for Offline Use
Related Page: Remote Access and Granting Library Access
What Can I Do About It?
Turn Off Video Preview Thumbnails Generation
Since video preview thumbnails are one of the most common reasons for large directories, disabling their generation can greatly reduce further growth of the directory.
Note that disabling the settings will not affect existing video preview thumbnails; only future items will be affected. (However, see below regarding existing items.)
Tip!: You can choose on a per-library basis whether video preview thumbnails are created for that library. So, if you want them for movie content but not TV episodes, you can do that.
Related Page: Video Preview Thumbnails
Delete Existing Video Preview Thumbnails
If you have existing video preview thumbnails that you no longer want, you can remove those. To do so:
- Edit the library for which you want to remove thumbnails (e.g. your Movies or TV library)
- Select the Advanced tab on the left
- Use the Delete Preview Thumbnails button
- Confirm that you want to delete them
After you confirm deletion, your Plex Media Server will go through your library content and remove the video preview thumbnails. Depending on your library size, this may take a while to complete.
Tip!: If you wish to remove the video preview thumbnails for more than one library, simply edit each one and choose to delete.
Note: You’ll want to make sure that you also turn off video preview thumbnail creation or else they’ll simply get re-generated.
Related Page: Editing Libraries
Relocate your Plex Media Server Data Directory
If the underlying issue is that you’re running out of space on a small boot drive, for instance, then the easiest solution is often simply to relocate the Plex Media Server data directory.
Tip!: When relocating the data directory, you should make sure you do so to an internal drive on your computer (hard drive or SSD). Moving to a network location or an external (e.g. USB) drive can result in poor, unexpected, or even completely broken behavior.
Windows
For Windows installations, you can change the LocalAppDataPath advanced, hidden server setting. Refer to information about that setting for details.
Related Page: Advanced, Hidden Server Settings
macOS
The easiest way to re-locate the data directory on macOS is typically to use a standard symbolic link (symlink) to place the directory in another location and then point to it from the original location. It’s important to note that it needs to be an actual symlink and not an alias or shortcut.
Related Page: Symbolic Link (Wikipedia)
Linux
You can use a symbolic link on Linux similar to macOS (above), though the user and permissions situation on Linux often makes that more complicated. You can find more detailed information about how to re-locate the data directory in the forums.
Related Page: Forums: Moving PMS ‘Libarary’
Relocate your Sync Data Directory
If you need to move the directory used to store your processed sync files before they’re synced, you can use a standard symbolic link (symlink) to relocate the directory. It’s important to note that it needs to be an actual symlink and not an alias or shortcut.
The default location for the Sync data directory varies based on your OS:
Windows
%LOCALAPPDATA%\Plex Media Server\Cache\Transcode\Sync\OS X
~/Library/Caches/PlexMediaServer/Transcode/Sync/Linux
/var/lib/plexmediaserver/Library/Application Support/Plex Media Server/Cache/Transcode/Sync/Related Page: Symbolic Link (Wikipedia)