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core: dynamic fee algorithm from ArticMine

The fee will vary based on the base reward and the current
block size limit:

fee = (R/R0) * (M0/M) * F0

R: base reward
R0: reference base reward (10 monero)
M: block size limit
M0: minimum block size limit (60000)
F0: 0.002 monero

Starts applying at v4
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moneromooo-monero committed Oct 27, 2016
1 parent 83b0511 commit 82dbba10d467e28e56929e2e7f3b1f04d4635da4
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@@ -64,6 +64,8 @@
#define FEE_PER_KB_OLD ((uint64_t)10000000000) // pow(10, 10)
#define FEE_PER_KB ((uint64_t)2000000000) // 2 * pow(10, 9)
#define DYNAMIC_FEE_PER_KB_BASE_FEE ((uint64_t)2000000000) // 2 * pow(10,9)
#define DYNAMIC_FEE_PER_KB_BASE_BLOCK_REWARD ((uint64_t)10000000000000) // 10 * pow(10,12)
#define ORPHANED_BLOCKS_MAX_COUNT 100
@@ -122,6 +124,8 @@
#define THREAD_STACK_SIZE 5 * 1024 * 1024
#define HF_VERSION_DYNAMIC_FEE 4
// New constants are intended to go here
namespace config
{
@@ -46,6 +46,7 @@
#include "misc_language.h"
#include "profile_tools.h"
#include "file_io_utils.h"
#include "common/int-util.h"
#include "common/boost_serialization_helper.h"
#include "warnings.h"
#include "crypto/hash.h"
@@ -2708,6 +2709,57 @@ void Blockchain::check_ring_signature(const crypto::hash &tx_prefix_hash, const
result = crypto::check_ring_signature(tx_prefix_hash, key_image, p_output_keys, sig.data()) ? 1 : 0;
}
//------------------------------------------------------------------
uint64_t Blockchain::get_dynamic_per_kb_fee(uint64_t block_reward, size_t median_block_size)
{
if (median_block_size < CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2)
median_block_size = CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2;
uint64_t unscaled_fee_per_kb = (DYNAMIC_FEE_PER_KB_BASE_FEE * CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 / median_block_size);
uint64_t hi, lo = mul128(unscaled_fee_per_kb, block_reward, &hi);
static_assert(DYNAMIC_FEE_PER_KB_BASE_BLOCK_REWARD % 1000000 == 0, "DYNAMIC_FEE_PER_KB_BASE_BLOCK_REWARD must be divisible by 1000000");
static_assert(DYNAMIC_FEE_PER_KB_BASE_BLOCK_REWARD / 1000000 <= std::numeric_limits<uint32_t>::max(), "DYNAMIC_FEE_PER_KB_BASE_BLOCK_REWARD is too large");
// divide in two steps, since the divisor must be 32 bits, but DYNAMIC_FEE_PER_KB_BASE_BLOCK_REWARD isn't
div128_32(hi, lo, DYNAMIC_FEE_PER_KB_BASE_BLOCK_REWARD / 1000000, &hi, &lo);
div128_32(hi, lo, 1000000, &hi, &lo);
assert(hi == 0);
return lo;
}
//------------------------------------------------------------------
bool Blockchain::check_fee(size_t blob_size, uint64_t fee) const
{
const uint8_t version = get_current_hard_fork_version();
uint64_t fee_per_kb;
if (version < HF_VERSION_DYNAMIC_FEE)
{
fee_per_kb = FEE_PER_KB;
}
else
{
uint64_t median = m_current_block_cumul_sz_limit / 2;
uint64_t already_generated_coins = m_db->height() ? m_db->get_block_already_generated_coins(m_db->height() - 1) : 0;
uint64_t base_reward;
if (!get_block_reward(median, 1, already_generated_coins, base_reward, version))
return false;
fee_per_kb = get_dynamic_per_kb_fee(base_reward, median);
}
LOG_PRINT_L2("Using " << print_money(fee) << "/kB fee");
uint64_t needed_fee = blob_size / 1024;
needed_fee += (blob_size % 1024) ? 1 : 0;
needed_fee *= fee_per_kb;
if (fee < needed_fee)
{
LOG_PRINT_L1("transaction fee is not enough: " << print_money(fee) << ", minimum fee: " << print_money(needed_fee));
return false;
}
return true;
}
//------------------------------------------------------------------
// This function checks to see if a tx is unlocked. unlock_time is either
// a block index or a unix time.
@@ -512,6 +512,33 @@ namespace cryptonote
*/
bool check_tx_inputs(transaction& tx, uint64_t& pmax_used_block_height, crypto::hash& max_used_block_id, tx_verification_context &tvc, bool kept_by_block = false);
/**
* @brief get dynamic per kB fee for a given block size
*
* The dynamic fee is based on the block size in a past window, and
* the current block reward. It is expressed by kB.
*
* @param block_reward the current block reward
* @param median_block_size the median blob's size in the past window
*
* @return the per kB fee
*/
static uint64_t get_dynamic_per_kb_fee(uint64_t block_reward, size_t median_block_size);
/**
* @brief validate a transaction's fee
*
* This function validates the fee is enough for the transaction.
* This is based on the size of the transaction blob, and, after a
* height threshold, on the average size of transaction in a past window
*
* @param blob_size the transaction blob's size
* @param fee the fee
*
* @return true if the fee is enough, false otherwise
*/
bool check_fee(size_t blob_size, uint64_t fee) const;
/**
* @brief check that a transaction's outputs conform to current standards
*
@@ -133,12 +133,8 @@ namespace cryptonote
fee = tx.rct_signatures.txnFee;
}
uint64_t needed_fee = blob_size / 1024;
needed_fee += (blob_size % 1024) ? 1 : 0;
needed_fee *= FEE_PER_KB;
if (!kept_by_block && fee < needed_fee)
if (!kept_by_block && !m_blockchain.check_fee(blob_size, fee))
{
LOG_PRINT_L1("transaction fee is not enough: " << print_money(fee) << ", minimum fee: " << print_money(needed_fee));
tvc.m_verifivation_failed = true;
tvc.m_fee_too_low = true;
return false;
@@ -39,6 +39,7 @@ set(unit_tests_sources
dns_resolver.cpp
epee_boosted_tcp_server.cpp
epee_levin_protocol_handler_async.cpp
fee.cpp
get_xtype_from_string.cpp
main.cpp
mnemonics.cpp
View
@@ -0,0 +1,121 @@
// Copyright (c) 2014-2016, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
#include "gtest/gtest.h"
#include "cryptonote_core/blockchain.h"
using namespace cryptonote;
namespace
{
//--------------------------------------------------------------------------------------------------------------------
class fee : public ::testing::Test
{
};
TEST_F(fee, 10xmr)
{
// CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 and lower are clamped
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2), 2000000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 / 2), 2000000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 / 100), 2000000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, 1), 2000000000);
// higher is inverse proportional
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 2), 2000000000 / 2);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 10), 2000000000 / 10);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000), 2000000000 / 1000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(10000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000000ull), 2000000000 / 1000000);
}
TEST_F(fee, 1xmr)
{
// CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 and lower are clamped
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2), 200000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 / 2), 200000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 / 100), 200000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, 1), 200000000);
// higher is inverse proportional
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 2), 200000000 / 2);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 10), 200000000 / 10);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000), 200000000 / 1000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(1000000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000000ull), 200000000 / 1000000);
}
TEST_F(fee, dot3xmr)
{
// CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 and lower are clamped
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2), 60000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 / 2), 60000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 / 100), 60000000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, 1), 60000000);
// higher is inverse proportional
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 2), 60000000 / 2);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 10), 60000000 / 10);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000), 60000000 / 1000);
ASSERT_EQ(Blockchain::get_dynamic_per_kb_fee(300000000000, CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000000ull), 60000000 / 1000000);
}
static bool is_more_or_less(double x, double y)
{
return fabs(y - x) < 0.001;
}
static const double MAX_MULTIPLIER = 166.f;
TEST_F(fee, double_at_full)
{
static const uint64_t block_rewards[] = {
20000000000000ull, // 20 monero
13000000000000ull,
1000000000000ull,
600000000000ull, // .6 monero, minimum reward per block at 2min
300000000000ull, // .3 monero, minimum reward per block at 1min
};
static const uint64_t median_block_sizes[] = {
CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2,
CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 2,
CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 10,
CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000,
CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 1000000ull
};
for (uint64_t block_reward: block_rewards)
{
for (uint64_t median_block_size: median_block_sizes)
{
ASSERT_TRUE(is_more_or_less(Blockchain::get_dynamic_per_kb_fee(block_reward, median_block_size) * (median_block_size / 1024.) * MAX_MULTIPLIER / (double)block_reward, 1.992 * 1000 / 1024));
}
}
}
}

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