// Copyright 2021 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef INCLUDE_CPPGC_HEAP_STATISTICS_H_ #define INCLUDE_CPPGC_HEAP_STATISTICS_H_ #include #include #include #include namespace cppgc { /** * `HeapStatistics` contains memory consumption and utilization statistics for a * cppgc heap. */ struct HeapStatistics final { /** * Specifies the detail level of the heap statistics. Brief statistics contain * only the top-level allocated and used memory statistics for the entire * heap. Detailed statistics also contain a break down per space and page, as * well as freelist statistics and object type histograms. Note that used * memory reported by brief statistics and detailed statistics might differ * slightly. */ enum DetailLevel : uint8_t { kBrief, kDetailed, }; /** * Statistics of object types. For each type the statistics record its name, * how many objects of that type were allocated, and the overall size used by * these objects. */ struct ObjectStatistics { /** Number of distinct types in the heap. */ size_t num_types = 0; /** Name of each type in the heap. */ std::vector type_name; /** Number of allocated objects per each type. */ std::vector type_count; /** Overall size of allocated objects per each type. */ std::vector type_bytes; }; /** * Page granularity statistics. For each page the statistics record the * allocated memory size and overall used memory size for the page. */ struct PageStatistics { /** Overall amount of memory allocated for the page. */ size_t physical_size_bytes = 0; /** Amount of memory actually used on the page. */ size_t used_size_bytes = 0; }; /** * Statistics of the freelist (used only in non-large object spaces). For * each bucket in the freelist the statistics record the bucket size, the * number of freelist entries in the bucket, and the overall allocated memory * consumed by these freelist entries. */ struct FreeListStatistics { /** bucket sizes in the freelist. */ std::vector bucket_size; /** number of freelist entries per bucket. */ std::vector free_count; /** memory size consumed by freelist entries per size. */ std::vector free_size; }; /** * Space granularity statistics. For each space the statistics record the * space name, the amount of allocated memory and overall used memory for the * space. The statistics also contain statistics for each of the space's * pages, its freelist and the objects allocated on the space. */ struct SpaceStatistics { /** The space name */ std::string name; /** Overall amount of memory allocated for the space. */ size_t physical_size_bytes = 0; /** Amount of memory actually used on the space. */ size_t used_size_bytes = 0; /** Statistics for each of the pages in the space. */ std::vector page_stats; /** Statistics for the freelist of the space. */ FreeListStatistics free_list_stats; /** Statistics for object allocated on the space. Filled only when * NameProvider::HideInternalNames() is false. */ ObjectStatistics object_stats; }; /** Overall amount of memory allocated for the heap. */ size_t physical_size_bytes = 0; /** Amount of memory actually used on the heap. */ size_t used_size_bytes = 0; /** Detail level of this HeapStatistics. */ DetailLevel detail_level; /** Statistics for each of the spaces in the heap. Filled only when * detail_level is kDetailed. */ std::vector space_stats; }; } // namespace cppgc #endif // INCLUDE_CPPGC_HEAP_STATISTICS_H_