EOS每年增发1%的机制在系统合约中，其实说每年增发1%只是一年的总数，其实是只要在出块，EOS就在增发的路途中，下面分析一下增发的代码。
其实增发的1%的都是分给所有区块生产者的，只要出块了或者获得投票都有奖励，代码在producer_pay.cpp文件中，只有下面两个函数。
void system_contract::onblock( block_timestamp timestamp, account_name producer ) { using namespace eosio; require_auth(N(eosio)); /** until activated stake crosses this threshold no new rewards are paid */ if( _gstate.total_activated_stake < min_activated_stake ) return; if( _gstate.last_pervote_bucket_fill == 0 ) /// start the presses _gstate.last_pervote_bucket_fill = current_time(); /** * At startup the initial producer may not be one that is registered / elected * and therefore there may be no producer object for them. */ auto prod = _producers.find(producer); if ( prod != _producers.end() ) { _gstate.total_unpaid_blocks++; _producers.modify( prod, 0, [&](auto& p ) { p.unpaid_blocks++; }); } /// only update block producers once every minute, block_timestamp is in half seconds if( timestamp.slot - _gstate.last_producer_schedule_update.slot > 120 ) { update_elected_producers( timestamp ); if( (timestamp.slot - _gstate.last_name_close.slot) > blocks_per_day ) { name_bid_table bids(_self,_self); auto idx = bids.get_index<N(highbid)>(); auto highest = idx.begin(); if( highest != idx.end() && highest->high_bid > 0 && highest->last_bid_time < (current_time() - useconds_per_day) && _gstate.thresh_activated_stake_time > 0 && (current_time() - _gstate.thresh_activated_stake_time) > 14 * useconds_per_day ) { _gstate.last_name_close = timestamp; idx.modify( highest, 0, [&]( auto& b ){ b.high_bid = -b.high_bid; }); } } } }
这个onlock函数在每次生产者出块的时候都会被调用，见证者收到区块后也会调用(相当于验证区块)，每次生产者出块都会把该生产者的出块数进行统计，把所有的区块也进行统计，后面的代码不太清楚在做什么，后续再补充。
void system_contract::claimrewards( const account_name& owner ) {
require_auth(owner);
const auto& prod = _producers.get( owner );
eosio_assert( prod.active(), "producer does not have an active key" );
eosio_assert( _gstate.total_activated_stake >= min_activated_stake,
"cannot claim rewards until the chain is activated (at least 15% of all tokens participate in voting)" );
auto ct = current_time();
eosio_assert( ct - prod.last_claim_time > useconds_per_day, "already claimed rewards within past day" );
const asset token_supply = token( N(eosio.token)).get_supply(symbol_type(system_token_symbol).name() );
const auto usecs_since_last_fill = ct - _gstate.last_pervote_bucket_fill;
if( usecs_since_last_fill > 0 && _gstate.last_pervote_bucket_fill > 0 ) {
auto new_tokens = static_cast<int64_t>( (continuous_rate * double(token_supply.amount) * double(usecs_since_last_fill)) / double(useconds_per_year) );
auto to_producers = new_tokens / 5;
auto to_savings = new_tokens - to_producers;
auto to_per_block_pay = to_producers / 4;
auto to_per_vote_pay = to_producers - to_per_block_pay;
INLINE_ACTION_SENDER(eosio::token, issue)( N(eosio.token), {{N(eosio),N(active)}},
{N(eosio), asset(new_tokens), std::string("issue tokens for producer pay and savings")} );
INLINE_ACTION_SENDER(eosio::token, transfer)( N(eosio.token), {N(eosio),N(active)},
{ N(eosio), N(eosio.saving), asset(to_savings), "unallocated inflation" } );
INLINE_ACTION_SENDER(eosio::token, transfer)( N(eosio.token), {N(eosio),N(active)},
{ N(eosio), N(eosio.bpay), asset(to_per_block_pay), "fund per-block bucket" } );
INLINE_ACTION_SENDER(eosio::token, transfer)( N(eosio.token), {N(eosio),N(active)},
{ N(eosio), N(eosio.vpay), asset(to_per_vote_pay), "fund per-vote bucket" } );
_gstate.pervote_bucket += to_per_vote_pay;
_gstate.perblock_bucket += to_per_block_pay;
_gstate.last_pervote_bucket_fill = ct;
}
int64_t producer_per_block_pay = 0;
if( _gstate.total_unpaid_blocks > 0 ) {
producer_per_block_pay = (_gstate.perblock_bucket * prod.unpaid_blocks) / _gstate.total_unpaid_blocks;
}
int64_t producer_per_vote_pay = 0;
if( _gstate.total_producer_vote_weight > 0 ) {
producer_per_vote_pay = int64_t((_gstate.pervote_bucket * prod.total_votes ) / _gstate.total_producer_vote_weight);
}
if( producer_per_vote_pay < min_pervote_daily_pay ) {
producer_per_vote_pay = 0;
}
_gstate.pervote_bucket -= producer_per_vote_pay;
_gstate.perblock_bucket -= producer_per_block_pay;
_gstate.total_unpaid_blocks -= prod.unpaid_blocks;
_producers.modify( prod, 0, [&](auto& p) {
p.last_claim_time = ct;
p.unpaid_blocks = 0;
});
if( producer_per_block_pay > 0 ) {
INLINE_ACTION_SENDER(eosio::token, transfer)( N(eosio.token), {N(eosio.bpay),N(active)},
{ N(eosio.bpay), owner, asset(producer_per_block_pay), std::string("producer block pay") } );
}
if( producer_per_vote_pay > 0 ) {
INLINE_ACTION_SENDER(eosio::token, transfer)( N(eosio.token), {N(eosio.vpay),N(active)},
{ N(eosio.vpay), owner, asset(producer_per_vote_pay), std::string("producer vote pay") } );
}
}
} //namespace eosiosy
先理清一下概念：
_gstate.pervote_bucket //所有生产者获得投票的奖励资金
_gstate.perblock_bucket //所有出块的奖励资金
_gstate.total_unpaid_blocks //公链上还没有领取出块奖励的所有区块数
这里的做法是：
1.每个生产者至少每隔一天可以领取奖励；
2.出块的资金数目分为两部：把20%当做奖励发放给生产者；把80%放在了系统用户eosio.saving下面。
3.资金池为总数的20%，每个生产者领取的奖励计算方式： 生产者出块数 / 所有未领取奖励的区块数 * 25% + 生产者获得的投票数 / 公链上所有的投票数 * 75%（25%和75%的比例是指奖金池的比例）
4.因为是增发，所有eosio用户也会同步发行同等代币(总数的20%，)；
5.出块的奖励资金会临时放在系统用户eosio.bpay下， 获得的投票收益临时放在eosio.vpay用户下，但又马上转给了生产者，这样的设计暂时没有弄明白(为什么不直接转帐给生产者)。