It is not always possible to set all configurations from the GUI, especially for the daemon or the web interface. This guide will try to give an overview of how and what you can change. For the location of these files, look at the [Configuration Files](Configuration-Files.md) page.
_Note: Clicking the "Turtle" in the GUI when the [scheduler](#Scheduling) is enabled, will only temporarily remove the scheduled limit until the next cycle._
* **incomplete-dir-enabled:** Boolean (default = false) When enabled, new torrents will download the files to **incomplete-dir**. When complete, the files will be moved to **download-dir**.
* **preallocation:** Number (0 = Off, 1 = Fast, 2 = Full (slower but reduces disk fragmentation), default = 1)
* **umask:** Number (default = 18) Sets transmission's file mode creation mask. See [the umask(2) manpage](https://developer.apple.com/documentation/Darwin/Reference/ManPages/man2/umask.2.html) for more information. Users who want their saved torrents to be world-writable may want to set this value to 0. Bear in mind that the JSON markup language only accepts numbers in base 10, so the standard umask(2) octal notation "022" is written in settings.json as 18.
_Note: When **watch-dir-enabled** is true, only the transmission-daemon, transmission-gtk, and transmission-qt applications will monitor **watch-dir** for new .torrent files and automatically load them._
#### Misc
* **cache-size-mb:** Size (default = 4), in megabytes, to allocate for Transmission's memory cache. The cache is used to help batch disk IO together, so increasing the cache size can be used to reduce the number of disk reads and writes. Default is 2 if configured with --enable-lightweight.
* **encryption:** Number (0 = Prefer unencrypted connections, 1 = Prefer encrypted connections, 2 = Require encrypted connections; default = 1) [Encryption](https://wiki.vuze.com/w/Message_Stream_Encryption) preference. Encryption may help get around some ISP filtering, but at the cost of slightly higher CPU use.
* **lazy-bitfield-enabled:** Boolean (default = true) May help get around some ISP filtering. [Vuze specification](https://wiki.vuze.com/w/Commandline_options#Network_Options).
* **prefetch-enabled:** Boolean (default = true). When enabled, Transmission will hint to the OS which piece data it's about to read from disk in order to satisfy requests from peers. On Linux, this is done by passing `POSIX_FADV_WILLNEED` to [posix_fadvise()](https://www.kernel.org/doc/man-pages/online/pages/man2/posix_fadvise.2.html). On OS X, this is done by passing `F_RDADVISE` to [fcntl()](https://developer.apple.com/library/IOS/#documentation/System/Conceptual/ManPages_iPhoneOS/man2/fcntl.2.html). This defaults to false if configured with --enable-lightweight.
* **script-torrent-added-enabled:** Boolean (default = false) Run a script when a torrent is added to Transmission. Environmental variables are passed in as detailed on the [Scripts](./Scripts.md) page
* **script-torrent-added-filename:** String (default = "") Path to script.
* **script-torrent-done-enabled:** Boolean (default = false) Run a script when a torrent is done downloading. Environmental variables are passed in as detailed on the [Scripts](./Scripts.md) page
* **script-torrent-done-seeding-enabled:** Boolean (default = false) Run a script when a torrent is done seeding. Environmental variables are passed in as detailed on the [Scripts](./Scripts.md) page
* **script-torrent-done-seeding-filename:** String (default = "") Path to script.
* **peer-socket-tos:** String (default = "default") Set the [Type-Of-Service (TOS)](https://en.wikipedia.org/wiki/Type_of_Service) parameter for outgoing TCP packets. Possible values are "default", "lowcost", "throughput", "lowdelay" and "reliability". The value "lowcost" is recommended if you're using a smart router, and shouldn't harm in any case.
* **queue-stalled-enabled:** Boolean (default = true) When true, torrents that have not shared data for `queue-stalled-minutes` are treated as 'stalled' and are not counted against the `download-queue-size` and `seed-queue-size` limits.
* **rpc-bind-address:** String (default = "0.0.0.0") Where to listen for RPC connections
* **rpc-enabled:** Boolean (default = true)
* **rpc-host-whitelist:** String (Comma-delimited list of domain names. Wildcards allowed using '\*'. Example: "*.foo.org,example.com", Default: "", Always allowed: "localhost", "localhost.", all the IP addresses. Added in v2.93)
* **rpc-host-whitelist-enabled:** Boolean (default = true. Added in v2.93)
* **rpc-password:** String. You can enter this in as plaintext when Transmission is not running, and then Transmission will salt the value on startup and re-save the salted version as a security measure. **Note:** Transmission treats passwords starting with the character `{` as salted, so when you first create your password, the plaintext password you enter must not begin with `{`.
* **rpc-url:** String (default = /transmission/. Added in v2.2)
* **rpc-username:** String
* **rpc-whitelist:** String (Comma-delimited list of IP addresses. Wildcards allowed using '\*'. Example: "127.0.0.\*,192.168.\*.\*", Default: "127.0.0.1")
* **rpc-access-control-list:** String (Comma-delimited list of IP addresses prefixed with "+" or "-". Wildcards allowed using '\*'. Example: "+127.0.0.\*,-192.168.\*.\*", Default: "+127.0.0.1")
Mac OS X has a standardized way of saving user preferences files using [XML](https://en.wikipedia.org/wiki/XML) format. These files are called [plist](https://en.wikipedia.org/wiki/Plist) (short for property list) files. Usually there is no need to modify these files directly, since Apple provided a [command-line tool](https://developer.apple.com/DOCUMENTATION/Darwin/Reference/ManPages/man1/defaults.1.html) to reliably change settings. You do need to restart Transmission before these have effect.