🔑 MSIG for setinflation to 1%

Reference document for modifying inflation on an EOSIO chain.

• Proposer: eosnationftw
• Proposal Name: setinflation

Proposed on following Testnets:

• Kylin
• Jungle2
• Jungle3

Proposed Parameters

The following setinflation parameters would set the total inflation to 1% and nothing would flow into eosio.saving.

• Annual rate: 100 (1%)
• Inflation pay factor: 10000 (100%)
• Vote pay factor: 40000 (25%)

Action

JSON file for setinflation.json

cleos push action eosio setinflation '{"annual_rate":100, "inflation_pay_factor":10000, "votepay_factor":40000}' -p eosio

EOSIO code reference

Default Parameters

• Annual rate: 500 (5%)
• Inflation pay factor: 50000 (20%)
• Vote pay factor: 40000 (25%)

eosio.system.hpp#L73-L77

static constexpr int64_t  inflation_precision           = 100;     // 2 decimals
static constexpr int64_t  default_annual_rate           = 500;     // 5% annual rate
static constexpr int64_t  pay_factor_precision          = 10000;
static constexpr int64_t  default_inflation_pay_factor  = 50000;   // producers pay share = 10000 / 50000 = 20% of the inflation
static constexpr int64_t  default_votepay_factor        = 40000;   // per-block pay share = 10000 / 40000 = 25% of the producer pay

Producer Pay

• To Producers = new_tokens * pay_factor_precision / inflation_pay_factor;
• To Savings = new_tokens - to_producers

producer_pay.cpp#L85-L93

double additional_inflation = (_gstate4.continuous_rate * double(token_supply.amount) * double(usecs_since_last_fill)) / double(useconds_per_year);
check( additional_inflation <= double(std::numeric_limits<int64_t>::max() - ((1ll << 10) - 1)),
    "overflow in calculating new tokens to be issued; inflation rate is too high" );
int64_t new_tokens = (additional_inflation < 0.0) ? 0 : static_cast<int64_t>(additional_inflation);

int64_t to_producers     = (new_tokens * uint128_t(pay_factor_precision)) / _gstate4.inflation_pay_factor;
int64_t to_savings       = new_tokens - to_producers;
int64_t to_per_block_pay = (to_producers * uint128_t(pay_factor_precision)) / _gstate4.votepay_factor;
int64_t to_per_vote_pay  = to_producers - to_per_block_pay;

Set Inflation

Checks if inflation_pay_factor & votepay_factor is lower than 10000 (100%).

eosio.system.cpp#L298-L311

void system_contract::setinflation( int64_t annual_rate, int64_t inflation_pay_factor, int64_t votepay_factor ) {
    require_auth(get_self());
    check(annual_rate >= 0, "annual_rate can't be negative");
    if ( inflation_pay_factor < pay_factor_precision ) {
        check( false, "inflation_pay_factor must not be less than " + std::to_string(pay_factor_precision) );
    }
    if ( votepay_factor < pay_factor_precision ) {
        check( false, "votepay_factor must not be less than " + std::to_string(pay_factor_precision) );
    }
    _gstate4.continuous_rate      = get_continuous_rate(annual_rate);
    _gstate4.inflation_pay_factor = inflation_pay_factor;
    _gstate4.votepay_factor       = votepay_factor;
    _global4.set( _gstate4, get_self() );
}

Get Continous Rate

• 5% inflation = 0.04879016416943201
• 1% inflation = 0.009950330853168083

> Math.log1p(500 / (100 * 100))
0.04879016416943201
> Math.log1p(100 / (100 * 100))
0.009950330853168083

eosio.system.cpp#L15

double get_continuous_rate(int64_t annual_rate) {
    return std::log1p(double(annual_rate)/double(100*inflation_precision));
}