EOS新资源模型的介绍

EOS新资源模型的介绍

EOS主网即将在2个月后，迎来一次重大的升级： 上线新的资源分配模型。

我通过阅读源代码，去理解新资源模型的工作原理。

其源代码地址在EOS代码仓库的1.8.x-rentbw分支，链接为: rentbw.cpp

新资源模型，是更过更新系统合约，集成在eosio系统里的系统级资源租赁市场。

合约表结构

rent.state 数据库用于存储租赁市场的状态，类似市场的状态看板，租赁价格的计算，租借情况的计算，皆从这里来:

struct [[eosio::table("rent.state"),eosio::contract("eosio.system")]] rentbw_state { static constexpr uint32_t default_rent_days = 30; // 30 day resource rentals uint8_t version = 0; rentbw_state_resource net = {}; // NET market state rentbw_state_resource cpu = {}; // CPU market state uint32_t rent_days = default_rent_days; // `rentbw` `days` argument must match this. asset min_rent_fee = {}; // Rental fees below this amount are rejected uint64_t primary_key()const { return 0; } }; typedef eosio::singleton<"rent.state"_n, rentbw_state> rentbw_state_singleton;

其中的rentbw_state_resource是一个子级的数据结构,存储了cpu和net各自的市场状态和参数配置:

struct rentbw_state_resource { static constexpr double default_exponent = 2.0; // Exponent of 2.0 means that the price to rent a // tiny amount of resources increases linearly // with utilization. static constexpr uint32_t default_decay_secs = 1 * seconds_per_day; // 1 day; if 100% of bandwidth resources are in a // single loan, then, assuming no further renting, // 1 day after it expires the adjusted utilization // will be at approximately 37% and after 3 days // the adjusted utilization will be less than 5%. uint8_t version = 0; int64_t weight = 0; // resource market weight. calculated; varies over time. // 1 represents the same amount of resources as 1 // satoshi of SYS staked. int64_t weight_ratio = 0; // resource market weight ratio: // assumed_stake_weight / (assumed_stake_weight + weight). // calculated; varies over time. 1x = 10^15. 0.01x = 10^13. int64_t assumed_stake_weight = 0; // Assumed stake weight for ratio calculations. int64_t initial_weight_ratio = rentbw_frac; // Initial weight_ratio used for linear shrinkage. int64_t target_weight_ratio = rentbw_frac / 100; // Linearly shrink the weight_ratio to this amount. time_point_sec initial_timestamp = {}; // When weight_ratio shrinkage started time_point_sec target_timestamp = {}; // Stop automatic weight_ratio shrinkage at this time. Once this // time hits, weight_ratio will be target_weight_ratio. double exponent = default_exponent; // Exponent of resource price curve. uint32_t decay_secs = default_decay_secs; // Number of seconds for the gap between adjusted resource // utilization and instantaneous utilization to shrink by 63%. asset min_price = {}; // Fee needed to rent the entire resource market weight at // the minimum price (defaults to 0). asset max_price = {}; // Fee needed to rent the entire resource market weight at // the maximum price. int64_t utilization = 0; // Instantaneous resource utilization. This is the current // amount sold. utilization <= weight. int64_t adjusted_utilization = 0; // Adjusted resource utilization. This is >= utilization and // <= weight. It grows instantly but decays exponentially. time_point_sec utilization_timestamp = {}; // When adjusted_utilization was last updated // for modeling - not to merged in code int64_t fee = 0; };

系统配置, 存储了资源模型租赁算法的一些相关参数：

struct rentbw_config_resource { std::optional<int64_t> current_weight_ratio; // Immediately set weight_ratio to this amount. 1x = 10^15. 0.01x = 10^13. // Do not specify to preserve the existing setting or use the default; // this avoids sudden price jumps. For new chains which don't need // to gradually phase out staking and REX, 0.01x (10^13) is a good // value for both current_weight_ratio and target_weight_ratio. std::optional<int64_t> target_weight_ratio; // Linearly shrink weight_ratio to this amount. 1x = 10^15. 0.01x = 10^13. // Do not specify to preserve the existing setting or use the default. std::optional<int64_t> assumed_stake_weight; // Assumed stake weight for ratio calculations. Use the sum of total // staked and total rented by REX at the time the rentbw market // is first activated. Do not specify to preserve the existing // setting (no default exists); this avoids sudden price jumps. // For new chains which don't need to phase out staking and REX, // 10^12 is probably a good value. std::optional<time_point_sec> target_timestamp; // Stop automatic weight_ratio shrinkage at this time. Once this // time hits, weight_ratio will be target_weight_ratio. Ignored // if current_weight_ratio == target_weight_ratio. Do not specify // this to preserve the existing setting (no default exists). std::optional<double> exponent; // Exponent of resource price curve. Must be >= 1. Do not specify // to preserve the existing setting or use the default. std::optional<uint32_t> decay_secs; // Number of seconds for the gap between adjusted resource // utilization and instantaneous resource utilization to shrink // by 63%. Do not specify to preserve the existing setting or // use the default. std::optional<asset> min_price; // Fee needed to rent the entire resource market weight at the // minimum price. For example, this could be set to 0.005% of // total token supply. Do not specify to preserve the existing // setting or use the default. std::optional<asset> max_price; // Fee needed to rent the entire resource market weight at the // maximum price. For example, this could be set to 10% of total // token supply. Do not specify to preserve the existing // setting (no default exists). EOSLIB_SERIALIZE( rentbw_config_resource, (current_weight_ratio)(target_weight_ratio)(assumed_stake_weight) (target_timestamp)(exponent)(decay_secs)(min_price)(max_price) ) }; struct rentbw_config { rentbw_config_resource net; // NET market configuration rentbw_config_resource cpu; // CPU market configuration std::optional<uint32_t> rent_days; // `rentbw` `days` argument must match this. Do not specify to preserve the // existing setting or use the default. std::optional<asset> min_rent_fee; // Rental fees below this amount are rejected. Do not specify to preserve the // existing setting (no default exists). EOSLIB_SERIALIZE( rentbw_config, (net)(cpu)(rent_days)(min_rent_fee) ) };

rentbw.order租赁订单数据库，用于存储个人的租赁信息，比如租赁多少资源、租了多久，皆从这个表进行查询:

struct [[eosio::table("rentbw.order"),eosio::contract("eosio.system")]] rentbw_order { uint8_t version = 0; uint64_t id; name owner; int64_t net_weight; int64_t cpu_weight; time_point_sec expires; uint64_t primary_key()const { return id; } uint64_t by_owner()const { return owner.value; } uint64_t by_expires()const { return expires.utc_seconds; } }; typedef eosio::multi_index< "rentbw.order"_n, rentbw_order, indexed_by<"byowner"_n, const_mem_fun<rentbw_order, uint64_t, &rentbw_order::by_owner>>, indexed_by<"byexpires"_n, const_mem_fun<rentbw_order, uint64_t, &rentbw_order::by_expires>> > rentbw_order_table;

合约操作

相关Action一共有3:

第一个，是configrentbw，这是一个修改参数配置的动作，操作权限需要由21个超级节点多签通过才能执行。

/** * Configure the `rentbw` market. The market becomes available the first time this * action is invoked. */ [[eosio::action]] void configrentbw( rentbw_config& args );

第二个，是rentbwexec， 这是一个权限开放式的动作，任何人都可以调用它，去帮助完成租赁市场订单的处理和状态的更新。

/** * Process rentbw queue and update state. Action does not execute anything related to a specific user. * * @param user - any account can execute this action * @param max - number of queue items to process */ [[eosio::action]] void rentbwexec( const name& user, uint16_t max );

第三个，是rentbw， 这是用户操作入口，通过这个入口，去执行租用的租赁，可以指定要租多少，租多久，以及最大预算是多少：

/** * Rent NET and CPU * * @param payer - the resource buyer * @param receiver - the resource receiver * @param days - number of days of resource availability. Must match market configuration. * @param net_frac - fraction of net (100% = 10^15) managed by this market * @param cpu_frac - fraction of cpu (100% = 10^15) managed by this market * @param max_payment - the maximum amount `payer` is willing to pay. Tokens are withdrawn from * `payer`'s token balance. */ [[eosio::action]] void rentbw( const name& payer, const name& receiver, uint32_t days, int64_t net_frac, int64_t cpu_frac, const asset& max_payment );

资源租赁市场是一个了不起的创新

EOS公链的了不起之处，是把一切可以 “市场化” 的资源，都进行了市场化。

将账号，抽象成可以拍卖转让的唯一id资源(类似NFT)。

将主网的存储资源抽象成 RAM，可以在RAM市场中买卖。

将主网的操作执行时间、数据传输量抽象成CPU、NET，可以在市场中租赁。

这样的创新，其实是对经济学深刻的理解和表达。

这比起那些还滞留在gas消耗模型的公链里，是一种降维打击。

当然，这样精细化的设计，难免带来系统复杂度。普通用户要理解这些设计并不容易。

项目方要追求的，是能对普通用户隐藏这些公链底层的细节。

而本次的新资源模型，将为EOS公链DAPP易用性的提升，带来一个质的飞跃。

新资源模型对项目方和用户的意义

如果把主网的cpu、net可分配资源视为一张大饼。

那么，任何个人或者项目方，可以通过新的租赁市场。付费租下这块大饼的指定百分比。

比如DFS，是目前主网上一个较大的DApp开发商。服务于几千个EOS用户。

那么我们会预算去租下5%的主网资源，去为用户提供更好的服务。而用户，只要是在DFS应用里做任何操作，都可以无需担心cpu和net资源。

这是对DApp或DeFi应用的普及，有着重大意义的大利好。

他可以进一步降低普通用户的参与门槛。

对DApp用户而言

进一步降低了用户使用DApp的门槛。如果项目方愿意承担CPU成本的话，用户完全可以像使用互联网产品一样，顺畅的使用DApp。

这是一次公链资源模型的巨大变革。

那些来不及学习的公链、还停留在所有操作都燃烧代币的gas模型时代的公链，在易用性门槛这个条件上，将被EOS打得毫无还手之力。

对EOS持有者而言

EOS持有者，可以通过买入REX，去获得租赁市场的收入，如同地主，坐地收租，持有EOS买入REX，不仅可以参与主网节点投票，执行投票权，还能源源不断的享受公链上产生的经济收入。

总结

新资源模型，不是一个简单的改动。不是为了把EOS主网设计复杂化。

我们需要理解它的设计原理和初衷：

它是从经济学上入手，对系统的各个角色的需求进行全面的分析后，而设计出来的一个闭环的经济模型。

是从用户、项目方、EOS持有者、公链资源分配，多个维度的需求出发，作出的经济模型。

它要复杂度有复杂度，是一个闭环的经济模型，有订单、有队列、有价格算法、同时系统产生的支出和收益的分配得当。

要易用性有易用性，用户甚至都不需要关心细节，而dapp项目方也可以基于这个特性，提供基于vip的不同等级的服务。

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编译者/作者：DFS大丰收

玩币族申明：玩币族作为开放的资讯翻译/分享平台，所提供的所有资讯仅代表作者个人观点，与玩币族平台立场无关，且不构成任何投资理财建议。文章版权归原作者所有。