Function testMmapMemoryAllocation

bolt/common/memory/tests/MemoryPoolTest.cpp:313–363

}

void testMmapMemoryAllocation(
    int64_t capacity,
    MachinePageCount allocPages,
    size_t allocCount,
    bool threadSafe) {
  MemoryManager::Options options;
  options.allocatorCapacity = capacity;
  options.useMmapAllocator = true;
  MemoryManager manager{options};
  const auto kPageSize = 4 * KB;

  auto root = manager.addRootPool();
  auto child = root->addLeafChild("elastic_quota", threadSafe);

  std::vector<void*> allocations;
  uint64_t totalPageAllocated = 0;
  uint64_t totalPageMapped = 0;
  auto* mmapAllocator = static_cast<MmapAllocator*>(manager.allocator());
  const auto pageIncrement = numPagesNeeded(mmapAllocator, allocPages);
  const auto isSizeClassAlloc =
      allocPages <= mmapAllocator->sizeClasses().back();
  const auto byteSize = allocPages * kPageSize;
  const std::string buffer(byteSize, 'x');
  for (size_t i = 0; i < allocCount; i++) {
    void* allocResult = nullptr;
    ASSERT_NO_THROW(allocResult = child->allocate(byteSize));
    ASSERT_TRUE(allocResult != nullptr);

    // Write data to let mapped address to be backed by physical memory
    memcpy(allocResult, buffer.data(), byteSize);
    allocations.emplace_back(allocResult);
    totalPageAllocated += pageIncrement;
    totalPageMapped += pageIncrement;
    ASSERT_EQ(mmapAllocator->numAllocated(), totalPageAllocated);
    ASSERT_EQ(
        isSizeClassAlloc ? mmapAllocator->numMapped()
                         : mmapAllocator->numExternalMapped(),
        totalPageMapped);
  }
  for (size_t i = 0; i < allocCount; i++) {
    ASSERT_NO_THROW(child->free(allocations[i], byteSize));
    totalPageAllocated -= pageIncrement;
    ASSERT_EQ(mmapAllocator->numAllocated(), totalPageAllocated);
    if (isSizeClassAlloc) {
      ASSERT_EQ(mmapAllocator->numMapped(), totalPageMapped);
    } else {
      totalPageMapped -= pageIncrement;
      ASSERT_EQ(mmapAllocator->numExternalMapped(), totalPageMapped);
    }
  }
}

TEST_P(MemoryPoolTest, smallMmapMemoryAllocation) {
  testMmapMemoryAllocation(8 * GB, 6, 100, isLeafThreadSafe_);