Link inflation calculations source (polkadot-js#8182)

* Link inflation calculations * Update packages/react-hooks/src/useInflation.ts
tolgaouz · Sep 29, 2022 · f2e6578 · f2e6578
1 parent 0701ece
commit f2e6578
Show file tree

Hide file tree

Showing 2 changed files with 12 additions and 0 deletions.
diff --git a/packages/apps-config/src/api/params/inflation.ts b/packages/apps-config/src/api/params/inflation.ts
@@ -17,14 +17,22 @@ interface InflationParams {
 const DEFAULT_PARAMS: InflationParams = {
   auctionAdjust: 0,
   auctionMax: 0,
+  // 5% for falloff, as per the defaults, see
+  // https://github.com/paritytech/polkadot/blob/816cb64ea16102c6c79f6be2a917d832d98df757/runtime/kusama/src/lib.rs#L534
   falloff: 0.05,
+  // 10% max, 0.25% min, see
+  // https://github.com/paritytech/polkadot/blob/816cb64ea16102c6c79f6be2a917d832d98df757/runtime/kusama/src/lib.rs#L523
   maxInflation: 0.1,
   minInflation: 0.025,
   stakeTarget: 0.5
 };
 
 const KNOWN_PARAMS: Record<string, InflationParams> = {
   [DOCK_POS_TESTNET_GENESIS]: { ...DEFAULT_PARAMS, stakeTarget: 0.75 },
+  // 30% for up to 60 slots, see
+  // https://github.com/paritytech/polkadot/blob/816cb64ea16102c6c79f6be2a917d832d98df757/runtime/kusama/src/lib.rs#L526-L527
+  // 75% ideal target, see
+  // https://github.com/paritytech/polkadot/blob/816cb64ea16102c6c79f6be2a917d832d98df757/runtime/kusama/src/lib.rs#L529-L531
   [KUSAMA_GENESIS]: { ...DEFAULT_PARAMS, auctionAdjust: (0.3 / 60), auctionMax: 60, stakeTarget: 0.75 },
   [NEATCOIN_GENESIS]: { ...DEFAULT_PARAMS, stakeTarget: 0.75 },
   [NFTMART_GENESIS]: { ...DEFAULT_PARAMS, falloff: 0.04, stakeTarget: 0.60 },

diff --git a/packages/react-hooks/src/useInflation.ts b/packages/react-hooks/src/useInflation.ts
@@ -21,8 +21,12 @@ function calcInflation (api: ApiPromise, totalStaked: BN, totalIssuance: BN, num
   const stakedFraction = totalStaked.isZero() || totalIssuance.isZero()
     ? 0
     : totalStaked.mul(BN_MILLION).div(totalIssuance).toNumber() / BN_MILLION.toNumber();
+  // Ideal is less based on the actual auctions, see
+  // https://github.com/paritytech/polkadot/blob/816cb64ea16102c6c79f6be2a917d832d98df757/runtime/kusama/src/lib.rs#L531
   const idealStake = stakeTarget - (Math.min(auctionMax, numAuctions.toNumber()) * auctionAdjust);
   const idealInterest = maxInflation / idealStake;
+  // inflation calculations, see
+  // https://github.com/paritytech/substrate/blob/0ba251c9388452c879bfcca425ada66f1f9bc802/frame/staking/reward-fn/src/lib.rs#L28-L54
   const inflation = 100 * (minInflation + (
     stakedFraction <= idealStake
       ? (stakedFraction * (idealInterest - (minInflation / idealStake)))