aboutsummaryrefslogtreecommitdiff
path: root/src/test/validation_flush_tests.cpp
blob: 9136c497ea004a797c6b28a8ce9413f00c97a0b0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
// Copyright (c) 2019-2020 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
//
#include <sync.h>
#include <test/util/setup_common.h>
#include <txmempool.h>
#include <validation.h>

#include <boost/test/unit_test.hpp>

BOOST_FIXTURE_TEST_SUITE(validation_flush_tests, ChainTestingSetup)

//! Test utilities for detecting when we need to flush the coins cache based
//! on estimated memory usage.
//!
//! @sa CChainState::GetCoinsCacheSizeState()
//!
BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
{
    CTxMemPool mempool;
    BlockManager blockman{};
    CChainState chainstate{&mempool, blockman, *Assert(m_node.chainman)};
    chainstate.InitCoinsDB(/*cache_size_bytes*/ 1 << 10, /*in_memory*/ true, /*should_wipe*/ false);
    WITH_LOCK(::cs_main, chainstate.InitCoinsCache(1 << 10));

    constexpr bool is_64_bit = sizeof(void*) == 8;

    LOCK(::cs_main);
    auto& view = chainstate.CoinsTip();

    //! Create and add a Coin with DynamicMemoryUsage of 80 bytes to the given view.
    auto add_coin = [](CCoinsViewCache& coins_view) -> COutPoint {
        Coin newcoin;
        uint256 txid = InsecureRand256();
        COutPoint outp{txid, 0};
        newcoin.nHeight = 1;
        newcoin.out.nValue = InsecureRand32();
        newcoin.out.scriptPubKey.assign((uint32_t)56, 1);
        coins_view.AddCoin(outp, std::move(newcoin), false);

        return outp;
    };

    // The number of bytes consumed by coin's heap data, i.e. CScript
    // (prevector<28, unsigned char>) when assigned 56 bytes of data per above.
    //
    // See also: Coin::DynamicMemoryUsage().
    constexpr unsigned int COIN_SIZE = is_64_bit ? 80 : 64;

    auto print_view_mem_usage = [](CCoinsViewCache& view) {
        BOOST_TEST_MESSAGE("CCoinsViewCache memory usage: " << view.DynamicMemoryUsage());
    };

    constexpr size_t MAX_COINS_CACHE_BYTES = 1024;

    // Without any coins in the cache, we shouldn't need to flush.
    BOOST_CHECK_EQUAL(
        chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
        CoinsCacheSizeState::OK);

    // If the initial memory allocations of cacheCoins don't match these common
    // cases, we can't really continue to make assertions about memory usage.
    // End the test early.
    if (view.DynamicMemoryUsage() != 32 && view.DynamicMemoryUsage() != 16) {
        // Add a bunch of coins to see that we at least flip over to CRITICAL.

        for (int i{0}; i < 1000; ++i) {
            COutPoint res = add_coin(view);
            BOOST_CHECK_EQUAL(view.AccessCoin(res).DynamicMemoryUsage(), COIN_SIZE);
        }

        BOOST_CHECK_EQUAL(
            chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
            CoinsCacheSizeState::CRITICAL);

        BOOST_TEST_MESSAGE("Exiting cache flush tests early due to unsupported arch");
        return;
    }

    print_view_mem_usage(view);
    BOOST_CHECK_EQUAL(view.DynamicMemoryUsage(), is_64_bit ? 32U : 16U);

    // We should be able to add COINS_UNTIL_CRITICAL coins to the cache before going CRITICAL.
    // This is contingent not only on the dynamic memory usage of the Coins
    // that we're adding (COIN_SIZE bytes per), but also on how much memory the
    // cacheCoins (unordered_map) preallocates.
    constexpr int COINS_UNTIL_CRITICAL{3};

    for (int i{0}; i < COINS_UNTIL_CRITICAL; ++i) {
        COutPoint res = add_coin(view);
        print_view_mem_usage(view);
        BOOST_CHECK_EQUAL(view.AccessCoin(res).DynamicMemoryUsage(), COIN_SIZE);
        BOOST_CHECK_EQUAL(
            chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
            CoinsCacheSizeState::OK);
    }

    // Adding some additional coins will push us over the edge to CRITICAL.
    for (int i{0}; i < 4; ++i) {
        add_coin(view);
        print_view_mem_usage(view);
        if (chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0) ==
            CoinsCacheSizeState::CRITICAL) {
            break;
        }
    }

    BOOST_CHECK_EQUAL(
        chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
        CoinsCacheSizeState::CRITICAL);

    // Passing non-zero max mempool usage should allow us more headroom.
    BOOST_CHECK_EQUAL(
        chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
        CoinsCacheSizeState::OK);

    for (int i{0}; i < 3; ++i) {
        add_coin(view);
        print_view_mem_usage(view);
        BOOST_CHECK_EQUAL(
            chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
            CoinsCacheSizeState::OK);
    }

    // Adding another coin with the additional mempool room will put us >90%
    // but not yet critical.
    add_coin(view);
    print_view_mem_usage(view);

    // Only perform these checks on 64 bit hosts; I haven't done the math for 32.
    if (is_64_bit) {
        float usage_percentage = (float)view.DynamicMemoryUsage() / (MAX_COINS_CACHE_BYTES + (1 << 10));
        BOOST_TEST_MESSAGE("CoinsTip usage percentage: " << usage_percentage);
        BOOST_CHECK(usage_percentage >= 0.9);
        BOOST_CHECK(usage_percentage < 1);
        BOOST_CHECK_EQUAL(
            chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 1 << 10),
            CoinsCacheSizeState::LARGE);
    }

    // Using the default max_* values permits way more coins to be added.
    for (int i{0}; i < 1000; ++i) {
        add_coin(view);
        BOOST_CHECK_EQUAL(
            chainstate.GetCoinsCacheSizeState(),
            CoinsCacheSizeState::OK);
    }

    // Flushing the view doesn't take us back to OK because cacheCoins has
    // preallocated memory that doesn't get reclaimed even after flush.

    BOOST_CHECK_EQUAL(
        chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 0),
        CoinsCacheSizeState::CRITICAL);

    view.SetBestBlock(InsecureRand256());
    BOOST_CHECK(view.Flush());
    print_view_mem_usage(view);

    BOOST_CHECK_EQUAL(
        chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 0),
        CoinsCacheSizeState::CRITICAL);
}

BOOST_AUTO_TEST_SUITE_END()