2 minute read.Last Modified 2021-07-30 09:07 EDT
TrueNAS allows you to add system tunables from the web interface. These can be manually defined or TrueNAS can run an autotuning script to attempt to optimize the system. Tunables are used to manage TrueNAS sysctls, loaders, and rc.conf options.
- loader : specifies parameters to pass to the kernel or load additional modules at boot time.
- rc.conf : enables system services and daemons and only take effect after a reboot.
- sysctl : configures kernel parameters while the system is running and generally take effect immediately.
Adding a sysctl, loader, or
rc.confoption is an advanced feature. A sysctl immediately affects the kernel running the TrueNAS system and a loader could adversely affect the ability of the TrueNAS system to successfully boot. Do not create a tunable on a production system before testing the ramifications of that change.
To configure a tunable, go to System > Tunables and click ADD.
First, select the Type of tunable to add or modify. Enter the name of the loader, sysctl, or rc.conf variable to configure.
If you wish to create the system tunable but not immediately enable it, unset the Enable checkbox. Configured tunables remain in effect until deleted or Enabled is unset.
Restarting the TrueNAS system after making sysctl changes is recommended. Some sysctls only take effect at system startup, and restarting the system guarantees that the setting values correspond with what is being used by the running system.
Be careful when adding or editing the default tunables. Changing the default tunables can make the system unusable.
|Variable||Enter the name of the loader, |
|Value||Enter a value to use for the loader, sysctl, or rc.conf variable.|
|Type||Creating or editing a sysctl immediately updates the Variable to the configured Value. A restart is required to apply loader or |
|Description||Enter a description of the tunable.|
|Enabled||Enable this tunable. Unset to disable this tunable without deleting it.|