/ src / test / validation_flush_tests.cpp
validation_flush_tests.cpp
  1  // Copyright (c) 2019-2022 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/coins.h>
  7  #include <test/util/random.h>
  8  #include <test/util/setup_common.h>
  9  #include <validation.h>
 10  
 11  #include <boost/test/unit_test.hpp>
 12  
 13  BOOST_FIXTURE_TEST_SUITE(validation_flush_tests, TestingSetup)
 14  
 15  //! Test utilities for detecting when we need to flush the coins cache based
 16  //! on estimated memory usage.
 17  //!
 18  //! @sa Chainstate::GetCoinsCacheSizeState()
 19  //!
 20  BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
 21  {
 22      Chainstate& chainstate{m_node.chainman->ActiveChainstate()};
 23  
 24      constexpr bool is_64_bit = sizeof(void*) == 8;
 25  
 26      LOCK(::cs_main);
 27      auto& view = chainstate.CoinsTip();
 28  
 29      // The number of bytes consumed by coin's heap data, i.e. CScript
 30      // (prevector<28, unsigned char>) when assigned 56 bytes of data per above.
 31      //
 32      // See also: Coin::DynamicMemoryUsage().
 33      constexpr unsigned int COIN_SIZE = is_64_bit ? 80 : 64;
 34  
 35      auto print_view_mem_usage = [](CCoinsViewCache& view) {
 36          BOOST_TEST_MESSAGE("CCoinsViewCache memory usage: " << view.DynamicMemoryUsage());
 37      };
 38  
 39      // PoolResource defaults to 256 KiB that will be allocated, so we'll take that and make it a bit larger.
 40      constexpr size_t MAX_COINS_CACHE_BYTES = 262144 + 512;
 41  
 42      // Without any coins in the cache, we shouldn't need to flush.
 43      BOOST_TEST(
 44          chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes=*/ 0) != CoinsCacheSizeState::CRITICAL);
 45  
 46      // If the initial memory allocations of cacheCoins don't match these common
 47      // cases, we can't really continue to make assertions about memory usage.
 48      // End the test early.
 49      if (view.DynamicMemoryUsage() != 32 && view.DynamicMemoryUsage() != 16) {
 50          // Add a bunch of coins to see that we at least flip over to CRITICAL.
 51  
 52          for (int i{0}; i < 1000; ++i) {
 53              const COutPoint res = AddTestCoin(view);
 54              BOOST_CHECK_EQUAL(view.AccessCoin(res).DynamicMemoryUsage(), COIN_SIZE);
 55          }
 56  
 57          BOOST_CHECK_EQUAL(
 58              chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes=*/0),
 59              CoinsCacheSizeState::CRITICAL);
 60  
 61          BOOST_TEST_MESSAGE("Exiting cache flush tests early due to unsupported arch");
 62          return;
 63      }
 64  
 65      print_view_mem_usage(view);
 66      BOOST_CHECK_EQUAL(view.DynamicMemoryUsage(), is_64_bit ? 32U : 16U);
 67  
 68      // We should be able to add COINS_UNTIL_CRITICAL coins to the cache before going CRITICAL.
 69      // This is contingent not only on the dynamic memory usage of the Coins
 70      // that we're adding (COIN_SIZE bytes per), but also on how much memory the
 71      // cacheCoins (unordered_map) preallocates.
 72      constexpr int COINS_UNTIL_CRITICAL{3};
 73  
 74      // no coin added, so we have plenty of space left.
 75      BOOST_CHECK_EQUAL(
 76          chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
 77          CoinsCacheSizeState::OK);
 78  
 79      for (int i{0}; i < COINS_UNTIL_CRITICAL; ++i) {
 80          const COutPoint res = AddTestCoin(view);
 81          print_view_mem_usage(view);
 82          BOOST_CHECK_EQUAL(view.AccessCoin(res).DynamicMemoryUsage(), COIN_SIZE);
 83  
 84          // adding first coin causes the MemoryResource to allocate one 256 KiB chunk of memory,
 85          // pushing us immediately over to LARGE
 86          BOOST_CHECK_EQUAL(
 87              chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes=*/ 0),
 88              CoinsCacheSizeState::LARGE);
 89      }
 90  
 91      // Adding some additional coins will push us over the edge to CRITICAL.
 92      for (int i{0}; i < 4; ++i) {
 93          AddTestCoin(view);
 94          print_view_mem_usage(view);
 95          if (chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes=*/0) ==
 96              CoinsCacheSizeState::CRITICAL) {
 97              break;
 98          }
 99      }
100  
101      BOOST_CHECK_EQUAL(
102          chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes=*/0),
103          CoinsCacheSizeState::CRITICAL);
104  
105      // Passing non-zero max mempool usage (512 KiB) should allow us more headroom.
106      BOOST_CHECK_EQUAL(
107          chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes=*/ 1 << 19),
108          CoinsCacheSizeState::OK);
109  
110      for (int i{0}; i < 3; ++i) {
111          AddTestCoin(view);
112          print_view_mem_usage(view);
113          BOOST_CHECK_EQUAL(
114              chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes=*/ 1 << 19),
115              CoinsCacheSizeState::OK);
116      }
117  
118      // Adding another coin with the additional mempool room will put us >90%
119      // but not yet critical.
120      AddTestCoin(view);
121      print_view_mem_usage(view);
122  
123      // Only perform these checks on 64 bit hosts; I haven't done the math for 32.
124      if (is_64_bit) {
125          float usage_percentage = (float)view.DynamicMemoryUsage() / (MAX_COINS_CACHE_BYTES + (1 << 10));
126          BOOST_TEST_MESSAGE("CoinsTip usage percentage: " << usage_percentage);
127          BOOST_CHECK(usage_percentage >= 0.9);
128          BOOST_CHECK(usage_percentage < 1);
129          BOOST_CHECK_EQUAL(
130              chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10), // 1024
131              CoinsCacheSizeState::LARGE);
132      }
133  
134      // Using the default max_* values permits way more coins to be added.
135      for (int i{0}; i < 1000; ++i) {
136          AddTestCoin(view);
137          BOOST_CHECK_EQUAL(
138              chainstate.GetCoinsCacheSizeState(),
139              CoinsCacheSizeState::OK);
140      }
141  
142      // Flushing the view does take us back to OK because ReallocateCache() is called
143  
144      BOOST_CHECK_EQUAL(
145          chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 0),
146          CoinsCacheSizeState::CRITICAL);
147  
148      view.SetBestBlock(InsecureRand256());
149      BOOST_CHECK(view.Flush());
150      print_view_mem_usage(view);
151  
152      BOOST_CHECK_EQUAL(
153          chainstate.GetCoinsCacheSizeState(MAX_COINS_CACHE_BYTES, 0),
154          CoinsCacheSizeState::OK);
155  }
156  
157  BOOST_AUTO_TEST_SUITE_END()