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Collateral Auction Throttler

1. Summary

The CollateralAuctionThrottler is meant to recompute the onAuctionSystemCoinLimit for the LiquidationEngine according to the latest global debt supply.

The throttler inherits functionality from the IncreasingTreasuryReimbursement.

2. Contract Variables & Functions


  • updateDelay - minimum **** delay between updates
  • backupUpdateDelay - delay since the last update time after which backupLimitRecompute can be called
  • globalDebtPercentage - percentage of global debt taken into account in order to set LiquidationEngine.onAuctionSystemCoinLimit
  • minAuctionLimit - the minimum value that can be set for onAuctionSystemCoinLimit
  • lastUpdateTime - last timestamp when the onAuctionSystemCoinLimit was updated
  • liquidationEngine - the LiquidationEngine contract
  • safeEngine - the SAFEEngine contract
  • surplusHolders - list of surplus holders taken into account when recomputing theonAuctionSystemCoinLimit


  • modifyParameters - modify contract parameters
  • recomputeOnAuctionSystemCoinLimit(feeReceiver: address) - recompute and set the new onAuctionSystemCoinLimit
  • backupRecomputeOnAuctionSystemCoinLimit() - backup function for recomputing the onAuctionSystemCoinLimit in case of a severe delay since the last update

3. Walkthrough

recomputeOnAuctionSystemCoinLimit is the core function used to periodically recompute the onAuctionSystemCoinLimit and set it in the liquidationEngine. Anyone can call this function as long as at least updateDelay seconds have passed since the last update. The function rewards the caller with surplus coming from the treasury.

backupRecomputeOnAuctionSystemCoinLimit is a backup function that can be called if at least backupUpdateDelay seconds have passed since the lastUpdateTime. As the name mentions, it is meant to work as a backup in case recomputeOnAuctionSystemCoinLimit hasn't been called in a long time (e.g because of bugs).