Alias:
lerp
Contract Name:dss-lerp
Scope: One instance for each parameter
Technical docs: link
The Linear Interpolation Module (lerp) allows a governance parameter to be changed linearly over a fixed period of time.
The primary purpose of the lerp module is to enable Governance to change a parameter gradually using only a single executive vote. The duration over which the parameter is changed, the starting value, and final value of the parameter can be chosen for each instance of the lerp module.
The lerp contract has one method called tick(), which is permissionless and can be called by anyone. This updates the target parameter to be whatever value it should be at that moment. If the elapsed time is longer than the duration, calling tick() will finish the lerp by changing done to true and set the parameter to the end value.
Each lerp factory invocation creates a new contract which has the following properties:
The target contract in which a parameter is being changed.
The name of the parameter being changed.
The starting time of this lerp instance.
The starting value of that parameter.
The ending value of that parameter.
The duration over which this lerp instance will run for.
This refers to whether the given lerp instance is finished or not.
Typically, the start and end parameters are adjusted to represent the current state and the desired state for the protocol. Hence, a longer duration results in the parameter being suboptimal for a longer period of time. On the other hand, more gradual changes are desirable as the protocols users can adapt more easily.
When lerp is used to determine allocation of protocol earnings, such as setting the System Surplus Buffer, Governance should ensure that the desired rate of increase is not larger than the expected protocol earnings. If the desired rate is too high, the lerp has no effect.
Page last reviewed: 2022-09-18
Next review due: 2023-09-18