SIP-318: Market-specific Minimum Liquidity Ratio

Simple Summary

This SIP proposes allowing custom minimum liquidity ratios to be set for specific markets via SCCP.

Motivation

The core system has a concept of a "minimum liquidity ratio" which determines a maximum amount of credit capacity (i.e the amount of withdrawable stablecoins) for markets relative to the value of the total collateral that has been delegated to them. This is a risk parameter somewhat analagous to the issuance ratio for liquidity providers.

In anticipation of allowing existing integrators—and ultimately anyone—to connect market implementations with the core system, it would be valuable to allow governance to adjust this risk parameter depending on the specifics of a market's behavior.

Rationale

In practice, the global, default minimum liquidity ratio will be set to a conservative (high) value. Governance can assess risk mitigation factors implicit in a markets' implementation and use this functionality to reduce the minimum liquidity ratio for a specific market, increasing its capital efficiency.

Technical Specification

A mapping, mapping(uint128 => uint) customMinLiquidityRatioD18;, will be added to the SystemPoolConfiguration storage library, with a corresponding setter method. If a non-zero value is present in this mapping for the relevant market, that value will be used in place of minLiquidityRatioD18.

Test Cases

Relevant tests will be developed during implementation.

Configurable Values (Via SCCP)

This SIP will add a mapping customMinLiquidityRatioD18 of market ID to a percentage multiplier (1000000000000000000 represents 100%).

Copyright

Copyright and related rights waived via CC0.