1 // Copyright (c) 2019-2020 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 //
5 #include <sync.h>
6 #include <test/util/setup_common.h>
7 #include <txmempool.h>
8 #include <validation.h>
9
10 #include <boost/test/unit_test.hpp>
11
BOOST_FIXTURE_TEST_SUITE(validation_flush_tests,BasicTestingSetup)12 BOOST_FIXTURE_TEST_SUITE(validation_flush_tests, BasicTestingSetup)
13
14 //! Test utilities for detecting when we need to flush the coins cache based
15 //! on estimated memory usage.
16 //!
17 //! @sa CChainState::GetCoinsCacheSizeState()
18 //!
19 BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
20 {
21 CTxMemPool mempool;
22 BlockManager blockman{};
23 CChainState chainstate{&mempool, blockman};
24 chainstate.InitCoinsDB(/*cache_size_bytes*/ 1 << 10, /*in_memory*/ true, /*should_wipe*/ false);
25 WITH_LOCK(::cs_main, chainstate.InitCoinsCache(1 << 10));
26
27 constexpr bool is_64_bit = sizeof(void*) == 8;
28
29 LOCK(::cs_main);
30 auto& view = chainstate.CoinsTip();
31
32 //! Create and add a Coin with DynamicMemoryUsage of 80 bytes to the given view.
33 auto add_coin = [](CCoinsViewCache& coins_view) -> COutPoint {
34 Coin newcoin;
35 uint256 txid = InsecureRand256();
36 COutPoint outp{txid, 0};
37 newcoin.nHeight = 1;
38 newcoin.out.nValue = InsecureRand32();
39 newcoin.out.scriptPubKey.assign((uint32_t)56, 1);
40 coins_view.AddCoin(outp, std::move(newcoin), false);
41
42 return outp;
43 };
44
45 // The number of bytes consumed by coin's heap data, i.e. CScript
46 // (prevector<28, unsigned char>) when assigned 56 bytes of data per above.
47 //
48 // See also: Coin::DynamicMemoryUsage().
49 constexpr unsigned int COIN_SIZE = is_64_bit ? 80 : 64;
50
51 auto print_view_mem_usage = [](CCoinsViewCache& view) {
52 BOOST_TEST_MESSAGE("CCoinsViewCache memory usage: " << view.DynamicMemoryUsage());
53 };
54
55 constexpr size_t MAX_COINS_CACHE_BYTES = 1024;
56
57 // Without any coins in the cache, we shouldn't need to flush.
58 BOOST_CHECK_EQUAL(
59 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
60 CoinsCacheSizeState::OK);
61
62 // If the initial memory allocations of cacheCoins don't match these common
63 // cases, we can't really continue to make assertions about memory usage.
64 // End the test early.
65 if (view.DynamicMemoryUsage() != 32 && view.DynamicMemoryUsage() != 16) {
66 // Add a bunch of coins to see that we at least flip over to CRITICAL.
67
68 for (int i{0}; i < 1000; ++i) {
69 COutPoint res = add_coin(view);
70 BOOST_CHECK_EQUAL(view.AccessCoin(res).DynamicMemoryUsage(), COIN_SIZE);
71 }
72
73 BOOST_CHECK_EQUAL(
74 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
75 CoinsCacheSizeState::CRITICAL);
76
77 BOOST_TEST_MESSAGE("Exiting cache flush tests early due to unsupported arch");
78 return;
79 }
80
81 print_view_mem_usage(view);
82 BOOST_CHECK_EQUAL(view.DynamicMemoryUsage(), is_64_bit ? 32U : 16U);
83
84 // We should be able to add COINS_UNTIL_CRITICAL coins to the cache before going CRITICAL.
85 // This is contingent not only on the dynamic memory usage of the Coins
86 // that we're adding (COIN_SIZE bytes per), but also on how much memory the
87 // cacheCoins (unordered_map) preallocates.
88 constexpr int COINS_UNTIL_CRITICAL{3};
89
90 for (int i{0}; i < COINS_UNTIL_CRITICAL; ++i) {
91 COutPoint res = add_coin(view);
92 print_view_mem_usage(view);
93 BOOST_CHECK_EQUAL(view.AccessCoin(res).DynamicMemoryUsage(), COIN_SIZE);
94 BOOST_CHECK_EQUAL(
95 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
96 CoinsCacheSizeState::OK);
97 }
98
99 // Adding some additional coins will push us over the edge to CRITICAL.
100 for (int i{0}; i < 4; ++i) {
101 add_coin(view);
102 print_view_mem_usage(view);
103 if (chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0) ==
104 CoinsCacheSizeState::CRITICAL) {
105 break;
106 }
107 }
108
109 BOOST_CHECK_EQUAL(
110 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
111 CoinsCacheSizeState::CRITICAL);
112
113 // Passing non-zero max mempool usage should allow us more headroom.
114 BOOST_CHECK_EQUAL(
115 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
116 CoinsCacheSizeState::OK);
117
118 for (int i{0}; i < 3; ++i) {
119 add_coin(view);
120 print_view_mem_usage(view);
121 BOOST_CHECK_EQUAL(
122 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
123 CoinsCacheSizeState::OK);
124 }
125
126 // Adding another coin with the additional mempool room will put us >90%
127 // but not yet critical.
128 add_coin(view);
129 print_view_mem_usage(view);
130
131 // Only perform these checks on 64 bit hosts; I haven't done the math for 32.
132 if (is_64_bit) {
133 float usage_percentage = (float)view.DynamicMemoryUsage() / (MAX_COINS_CACHE_BYTES + (1 << 10));
134 BOOST_TEST_MESSAGE("CoinsTip usage percentage: " << usage_percentage);
135 BOOST_CHECK(usage_percentage >= 0.9);
136 BOOST_CHECK(usage_percentage < 1);
137 BOOST_CHECK_EQUAL(
138 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 1 << 10),
139 CoinsCacheSizeState::LARGE);
140 }
141
142 // Using the default max_* values permits way more coins to be added.
143 for (int i{0}; i < 1000; ++i) {
144 add_coin(view);
145 BOOST_CHECK_EQUAL(
146 chainstate.GetCoinsCacheSizeState(),
147 CoinsCacheSizeState::OK);
148 }
149
150 // Flushing the view doesn't take us back to OK because cacheCoins has
151 // preallocated memory that doesn't get reclaimed even after flush.
152
153 BOOST_CHECK_EQUAL(
154 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 0),
155 CoinsCacheSizeState::CRITICAL);
156
157 view.SetBestBlock(InsecureRand256());
158 BOOST_CHECK(view.Flush());
159 print_view_mem_usage(view);
160
161 BOOST_CHECK_EQUAL(
162 chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 0),
163 CoinsCacheSizeState::CRITICAL);
164 }
165
166 BOOST_AUTO_TEST_SUITE_END()
167