v8.getHeapStatistics()

• 返回: <Object>

返回具有以下属性的对象：

• total_heap_size <number>
• total_heap_size_executable <number>
• total_physical_size <number>
• total_available_size <number>
• used_heap_size <number>
• heap_size_limit <number>
• malloced_memory <number>
• peak_malloced_memory <number>
• does_zap_garbage <number>
• number_of_native_contexts <number>
• number_of_detached_contexts <number>

does_zap_garbage 是 0/​​1 布尔值，表示是否启用了 --zap_code_space 选项。 这使得 V8 使用位模式覆盖堆垃圾。 RSS 占用空间（常驻集大小）变得更大，因为它不断接触所有堆页面，这使得它们不太可能被操作系统换出。

number_of_native_contexts native_context 的值是当前活动的顶层上下文的数量。 随着时间的推移此数字的增加表示内存泄漏。

number_of_detached_contexts detached_context 的值是已分离但尚未垃圾回收的上下文数。 此数字非零表示潜在的内存泄漏。

{
  total_heap_size: 7326976,
  total_heap_size_executable: 4194304,
  total_physical_size: 7326976,
  total_available_size: 1152656,
  used_heap_size: 3476208,
  heap_size_limit: 1535115264,
  malloced_memory: 16384,
  peak_malloced_memory: 1127496,
  does_zap_garbage: 0,
  number_of_native_contexts: 1,
  number_of_detached_contexts: 0
}

• Returns: <Object>

Returns an object with the following properties:

• total_heap_size <number>
• total_heap_size_executable <number>
• total_physical_size <number>
• total_available_size <number>
• used_heap_size <number>
• heap_size_limit <number>
• malloced_memory <number>
• peak_malloced_memory <number>
• does_zap_garbage <number>
• number_of_native_contexts <number>
• number_of_detached_contexts <number>

does_zap_garbage is a 0/1 boolean, which signifies whether the --zap_code_space option is enabled or not. This makes V8 overwrite heap garbage with a bit pattern. The RSS footprint (resident set size) gets bigger because it continuously touches all heap pages and that makes them less likely to get swapped out by the operating system.

number_of_native_contexts The value of native_context is the number of the top-level contexts currently active. Increase of this number over time indicates a memory leak.

number_of_detached_contexts The value of detached_context is the number of contexts that were detached and not yet garbage collected. This number being non-zero indicates a potential memory leak.

{
  total_heap_size: 7326976,
  total_heap_size_executable: 4194304,
  total_physical_size: 7326976,
  total_available_size: 1152656,
  used_heap_size: 3476208,
  heap_size_limit: 1535115264,
  malloced_memory: 16384,
  peak_malloced_memory: 1127496,
  does_zap_garbage: 0,
  number_of_native_contexts: 1,
  number_of_detached_contexts: 0
}