* Site-wide settings like page titles can be set (and extended) on the root tree element in the CMS "Content" section (through the [siteconfig](/reference/siteconfig) API).
## _ss_environment.php
See [environment-management](/topics/environment-management).
## mysite/_config.php
This file is detected in each folder by `[api:ManifestBuilder]`. This way, every toplevel-folder (=module)
You can call most static methods from _config.php - classes will be loaded as required. Here's a list - **this is
incomplete - please add to it** *Try to keep it in alphabetical order too! :)*
| Call | | Description |
| ---- | | ----------- |
| Authenticator::register_authenticator($authenticator);| | Enable an authentication method (for more details see [security](/topics/security)). |
| Authenticator::set_default_authenticator($authenticator); | | Modify tab-order on login-form.|
| BasicAuth::disable() | | Disable basic authentication checking for dev sites (useful when testing credit card transaction post-backs etc) |
| BBCodeParser::disable_autolink_urls(); | | Disables plain hyperlinks from being turned into links when bbcode is parsed. |
| BlogEntry::allow_wysiwyg_editing(); | | Enable rich text editing for blog posts. |
| ContentNegotiator::set_encoding(string $encoding) | | The encoding charset to use - UTF-8 by default |
| ContentNegotiator::disable() | | Disables the negotiation of content type -usually used to stop it from rewriting the DOCTYPE of the document
| Debug::send_errors_to(string $email) | | Send live errors on your site to this address (site has to be in 'live' mode using Director::set_environment_type(live) for this to occur |
| Director::set_environment_type(string dev,test,live) | | Sets the environment type (e.g. dev site will show errors, live site hides them and displays a 500 error instead) |
| Director::set_dev_servers(array('localhost', 'dev.mysite.com)) | | Set servers that should be run in dev mode (see [debugging](debugging)) |
| Director::addRules(int priority, array rules) | | Create a number of URL rules to be checked against when SilverStripe tries to figure out how to display a page. See cms/_config.php for some examples. Note: Using ->something/ as the value for one of these will redirect the user to the something/ page. |
| Email::setAdminEmail(string $adminemail) | | Sets the admin email for the site, used if there is no From address specified, or when you call Email::getAdminEmail() |
| Email::send_all_emails_to(string $email) | | Sends all emails to this address. Useful for debugging your email sending functions |
| Email::cc_all_emails_to(string $email) | | Useful for CC'ing all emails to someone checking correspondence |
| Email::bcc_all_emails_to(string $email) | | BCC all emails to this address, similar to CC'ing emails (above) |
| MathSpamProtection::setEnabled() | | Adds a math spam question to all page comment forms |
| Security::encrypt_passwords($encrypt_passwords); | | Specify if you want store your passwords in clear text or encrypted (for more details see [security](/topics/security)) |
| Security::set_password_encryption_algorithm($algorithm, $use_salt);| | If you choose to encrypt your passwords, you can choose which algorithm is used to and if a salt should be used to increase the security level even more (for more details see [security](/topics/security)). |
| Security::setDefaultAdmin('admin','password'); | | Set default admin email and password, helpful for recovering your password |
| SSAkismet::setAPIKey(string $key) | | Enables use of the Akismet spam filter. The key must be a valid WordPress API key. |
| SSViewer::set_theme(string $themename) | | Choose the default theme for your site |
## Constants
Some constants are user-defineable within *_ss_environment.php*.
| Name | | Description |
| ---- | | ----------- |
| *TEMP_FOLDER* | | Absolute file path to store temporary files such as cached templates or the class manifest. Needs to be writeable by the webserver user. Defaults to *sys_get_temp_dir()*, and falls back to *silverstripe-cache* in the webroot. See *getTempFolder()* in *sapphire/core/Core.php* |
## User-level: Member-object
All user-related preferences are stored as a property of the `[api:Member]`-class (and as a database-column in the
*Member*-table). You can "mix in" your custom preferences by using `[api:DataObject]` for details.
## Permissions
See [security](/topics/security) and [permission](/reference/permission)
SilverStripe tries to keep its resource usage within the documented limits (see our [server requirements](../installation/server-requirements)).
These limits are defined through `memory_limit` and `max_execution_time` in the PHP configuration.
They can be overwritten through `ini_set()`, unless PHP is running with the [Suhoshin Patches](http://www.hardened-php.net/)
or in "[safe mode](http://php.net/manual/en/features.safe-mode.php)".
Most shared hosting providers will have maximum values that can't be altered.
For certain tasks like synchronizing a large `assets/` folder with all file and folder entries in the database,
more resources are required temporarily. In general, we recommend running resource intensive tasks
through the [commandline](../topics/commandline), where configuration defaults for these settings are higher or even unlimited.
SilverStripe can request more resources through `increase_memory_limit_to()` and `increase_time_limit_to()`.
If you are concerned about resource usage on a dedicated server (without restrictions imposed through shared hosting providers), you can set a hard limit to these increases through
`set_increase_memory_limit_max()` and `set_increase_time_limit_max()`.
These values will just be used for specific scripts (e.g. `[api:Filesystem::sync()]`),
to raise the limits for all executed scripts please use `ini_set('memory_limit', <value>)`
and `ini_set('max_execution_time', <value>)` in your own `_config.php`.
