monero/tests/unit_tests/output_selection.cpp
moneromooo-monero dbecfe7d5d
unit_tests: make the density test a bit less stringent
It's an inherently random test
2019-05-20 10:42:50 +00:00

220 lines
7.2 KiB
C++

// Copyright (c) 2014-2019, 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.
// FIXME: move this into a full wallet2 unit test suite, if possible
#include "gtest/gtest.h"
#include "wallet/wallet2.h"
#include <string>
static tools::wallet2::transfer_container make_transfers_container(size_t N)
{
tools::wallet2::transfer_container transfers;
for (size_t n = 0; n < N; ++n)
{
transfers.push_back(AUTO_VAL_INIT(tools::wallet2::transfer_details()));
tools::wallet2::transfer_details &td = transfers.back();
td.m_block_height = 1000;
td.m_spent = false;
td.m_txid = crypto::null_hash;
td.m_txid.data[0] = n & 0xff;
td.m_txid.data[1] = (n >> 8) & 0xff;
td.m_txid.data[2] = (n >> 16) & 0xff;
td.m_txid.data[3] = (n >> 24) & 0xff;
}
return transfers;
}
#define SELECT(idx) \
do { \
auto i = std::find(unused_indices.begin(), unused_indices.end(), idx); \
ASSERT_TRUE(i != unused_indices.end()); \
unused_indices.erase(i); \
selected.push_back(idx); \
} while(0)
#define PICK(expected) \
do { \
size_t idx = w.pop_best_value_from(transfers, unused_indices, selected); \
ASSERT_EQ(expected, idx); \
selected.push_back(idx); \
} while(0)
TEST(select_outputs, one_out_of_N)
{
tools::wallet2 w;
// check that if there are N-1 outputs of the same height, one of them
// already selected, the next one selected is the one that's from a
// different height
tools::wallet2::transfer_container transfers = make_transfers_container(10);
transfers[6].m_block_height = 700;
std::vector<size_t> unused_indices({0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
std::vector<size_t> selected;
SELECT(2);
PICK(6);
}
TEST(select_outputs, order)
{
tools::wallet2 w;
// check that most unrelated heights are picked in order
tools::wallet2::transfer_container transfers = make_transfers_container(5);
transfers[0].m_block_height = 700;
transfers[1].m_block_height = 700;
transfers[2].m_block_height = 704;
transfers[3].m_block_height = 716;
transfers[4].m_block_height = 701;
std::vector<size_t> unused_indices({0, 1, 2, 3, 4});
std::vector<size_t> selected;
SELECT(0);
PICK(3); // first the one that's far away
PICK(2); // then the one that's close
PICK(4); // then the one that's adjacent
PICK(1); // then the one that's on the same height
}
#define MKOFFSETS(N, n) \
offsets.resize(N); \
size_t n_outs = 0; \
for (auto &offset: offsets) \
{ \
offset = n_outs += (n); \
}
TEST(select_outputs, gamma)
{
std::vector<uint64_t> offsets;
MKOFFSETS(300000, 1);
tools::gamma_picker picker(offsets);
std::vector<double> ages(100000);
double age_scale = 120. * (offsets.size() / (double)n_outs);
for (size_t i = 0; i < ages.size(); )
{
uint64_t o = picker.pick();
if (o >= n_outs)
continue;
ages[i] = (n_outs - 1 - o) * age_scale;
ASSERT_GE(ages[i], 0);
ASSERT_LE(ages[i], offsets.size() * 120);
++i;
}
double median = epee::misc_utils::median(ages);
MDEBUG("median age: " << median / 86400. << " days");
ASSERT_GE(median, 1.3 * 86400);
ASSERT_LE(median, 1.4 * 86400);
}
TEST(select_outputs, density)
{
static const size_t NPICKS = 1000000;
std::vector<uint64_t> offsets;
MKOFFSETS(300000, 1 + (rand() & 0x1f));
tools::gamma_picker picker(offsets);
std::vector<int> picks(/*n_outs*/offsets.size(), 0);
for (int i = 0; i < NPICKS; )
{
uint64_t o = picker.pick();
if (o >= n_outs)
continue;
auto it = std::lower_bound(offsets.begin(), offsets.end(), o);
auto idx = std::distance(offsets.begin(), it);
ASSERT_LT(idx, picks.size());
++picks[idx];
++i;
}
for (int d = 1; d < 0x20; ++d)
{
// count the number of times an output in a block of d outputs was selected
// count how many outputs are in a block of d outputs
size_t count_selected = 0, count_chain = 0;
for (size_t i = 0; i < offsets.size(); ++i)
{
size_t n_outputs = offsets[i] - (i == 0 ? 0 : offsets[i - 1]);
if (n_outputs == d)
{
count_selected += picks[i];
count_chain += d;
}
}
float selected_ratio = count_selected / (float)NPICKS;
float chain_ratio = count_chain / (float)n_outs;
MDEBUG(count_selected << "/" << NPICKS << " outputs selected in blocks of density " << d << ", " << 100.0f * selected_ratio << "%");
MDEBUG(count_chain << "/" << offsets.size() << " outputs in blocks of density " << d << ", " << 100.0f * chain_ratio << "%");
ASSERT_LT(fabsf(selected_ratio - chain_ratio), 0.025f);
}
}
TEST(select_outputs, same_distribution)
{
static const size_t NPICKS = 1000000;
std::vector<uint64_t> offsets;
MKOFFSETS(300000, 1 + (rand() & 0x1f));
tools::gamma_picker picker(offsets);
std::vector<int> chain_picks(offsets.size(), 0);
std::vector<int> output_picks(n_outs, 0);
for (int i = 0; i < NPICKS; )
{
uint64_t o = picker.pick();
if (o >= n_outs)
continue;
auto it = std::lower_bound(offsets.begin(), offsets.end(), o);
auto idx = std::distance(offsets.begin(), it);
ASSERT_LT(idx, chain_picks.size());
++chain_picks[idx];
++output_picks[o];
++i;
}
// scale them both to 0-100
std::vector<int> chain_norm(100, 0), output_norm(100, 0);
for (size_t i = 0; i < output_picks.size(); ++i)
output_norm[i * 100 / output_picks.size()] += output_picks[i];
for (size_t i = 0; i < chain_picks.size(); ++i)
chain_norm[i * 100 / chain_picks.size()] += chain_picks[i];
double max_dev = 0.0, avg_dev = 0.0;
for (size_t i = 0; i < 100; ++i)
{
const double diff = (double)output_norm[i] - (double)chain_norm[i];
double dev = fabs(2.0 * diff / (output_norm[i] + chain_norm[i]));
ASSERT_LT(dev, 0.1);
avg_dev += dev;
}
avg_dev /= 100;
MDEBUG("avg_dev: " << avg_dev);
ASSERT_LT(avg_dev, 0.015);
}