Action Tiering

Some actions taken by governance are much more impactful and riskier than others.

To reflect these different levels of importance, every function that can be called through governance is assigned a tier. At the moment, the tiers implemented are:

Tier	Description
LOW	Small governance spending, fine-tuning
MEDIUM	Changes to parameters / system components that could have indirect safety implications
HIGH	Changes to parameters / system components that can have direct safety implications
CORE	Changes to the entire system / essentially upgrades
HIGH-TREASURY	Like HIGH but is not disabled when upgrades are disabled. For large treasury spending

A tier contains the following information:

• proposalThreshold: the minimum voting power required to create a proposal
• quorum: the quorum to be reached for the proposal to pass
• voteThreshold: the minimum ratio of for votes for the vote to pass
• timeLockDuration: the length of the time lock
• proposalLength: the length of the proposal
• actionLevel: how "impactful" the given action is

Assigning a tier is done using an ITierStrategy implementation and varies depending on the function called.

The following strategies are implemented:

• StaticTierStrategy: always returns the same tier regardless of the arguments
• SimpleThresholdStrategy: returns a tier based on whether one of the parameters is above a given threshold
• SetVaultFeesStrategy: Same as SimpleThresholdStrategy but compares two arguments to the threshold
• SetSystemParamsStrategy: Similar to SimpleThresholdStrategy but compares a several fields of a struct to multiple thresholds
• SetAddressStrategy: Has a different tier per address argument. This is used for the GyroConfig.setAddress that has the power to replace parts of the system.