Fortress Distribution Speeds
The “Fortress speed” unique to each market is an unsigned integer that specifies the amount of FTS that is distributed, per block, to suppliers and borrowers in each money market. As market conditions change, Fortress speeds are updated to ensure FTS is distributed proportional to the utility of each market. Any user can call the Unitroller’s refreshFortressSpeeds method at any time in order to update market Fortress speeds.
The following is the formula for calculating the rate that FTS is distributed to each supported market.
utility = fTokenTotalBorrows * assetPrice
utilityFraction = utility / sumOfAllFortressedMarketUtilities
marketFortressSpeed = fortressRate * utilityFraction


function refreshFortressSpeeds(address account) public
  • RETURN: None
  • events: FortressSpeedUpdated - An event is emitted for each fToken with the address of the fToken and the new FTS distribution speed per block.


Unitroller troll = Unitroller(0xABCD...);

Web3 1.0

const unitroller = new web3.eth.Contract(unitrollerAbi, unitrollerAddress);
await unitroller.methods.refreshFortressSpeeds().send({ from: sender });