Crate pallet_inflation

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§Inflation Handler Pallet

§Overview

This pallet’s main responsibility is handling inflation calculation & distribution.

Inflation configuration is calculated periodically, according to the inflation parameters. Based on this configuration, rewards are paid out - either per block or on demand.

§Cycles, Periods, Eras

At the start of each cycle, the inflation configuration is recalculated.

Cycle can be considered as a ‘year’ in the Astar network. When cycle starts, inflation is calculated according to the total issuance at that point in time. E.g. if ‘yearly’ inflation is set to be 7%, and total issuance is 200 ASTR, then the max inflation for that cycle will be 14 ASTR.

Each cycle consists of one or more periods. Periods are integral part of dApp staking protocol, allowing dApps to promote themselves, attract stakers and earn rewards. At the end of each period, all stakes are reset, and dApps need to repeat the process.

Each period consists of two subperiods: Voting and Build&Earn. Length of these subperiods is expressed in eras. An era is the core time unit in dApp staking protocol. When an era ends, in Build&Earn subperiod, rewards for dApps are calculated & assigned.

Era’s length is expressed in blocks. E.g. an era can last for 7200 blocks, which is approximately 1 day for 12 second block time.

Build&Earn subperiod length is expressed in eras. E.g. if Build&Earn subperiod lasts for 5 eras, it means that during that subperiod, dApp rewards will be calculated & assigned 5 times in total. Also, 5 distinct eras will change during that subperiod. If e.g. Build&Earn started at era 100, with 5 eras per Build&Earn subperiod, then the subperiod will end at era 105.

Voting subperiod always comes before Build&Earn subperiod. Its length is also expressed in eras, although it has to be interpreted a bit differently. Even though Voting can last for more than 1 era in respect of length, it always takes exactly 1 era. What this means is that if Voting lasts for 3 eras, and each era lasts 7200 blocks, then Voting will last for 21600 blocks. But unlike Build&Earn subperiod, Voting will only take up one ‘numerical’ era. So if Voting starts at era 110, it will end at era 11.

§Example
  • Cycle length: 4 periods
  • Voting length: 10 eras
  • Build&Earn length: 81 eras
  • Era length: 7200 blocks

This would mean that cycle lasts for roughly 364 days (4 * (10 + 81)).

§Recalculation

When new cycle begins, inflation configuration is recalculated according to the inflation parameters & total issuance at that point in time. Based on the max inflation rate, rewards for different network actors are calculated.

Some rewards are calculated to be paid out per block, while some are per era or per period.

§Rewards

§Collator & Treasury Rewards

These are paid out at the beginning of each block & are fixed amounts.

§Staker Rewards

Staker rewards are paid out per staker, on-demand. However, reward pool for an era is calculated at the end of each era.

era_reward_pool = base_staker_reward_pool_per_era + adjustable_staker_reward_pool_per_era

While the base staker reward pool is fixed, the adjustable part is calculated according to the total value staked & the ideal staking rate.

§dApp Rewards

dApp rewards are paid out per dApp, on-demand. The reward is decided by the dApp staking protocol, or the tier system to be more precise. This pallet only provides the total reward pool for all dApps per era.

§Interface

§StakingRewardHandler

This pallet implements StakingRewardHandler trait, which is used by the dApp staking protocol to get reward pools & distribute rewards.

Re-exports§

Modules§

  • migration
  • pallet
    The pallet module in each FRAME pallet hosts the most important items needed to construct this pallet.
  • weights
    Autogenerated weights for pallet_inflation

Structs§

Traits§

  • PayoutPerBlock
    Defines functions used to payout the beneficiaries of block rewards