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getHeapStatistics - node__v8.d.ts - Node documentation
function getHeapStatistics

Usage in Deno

```typescript import { getHeapStatistics } from "node:node__v8.d.ts"; ```
getHeapStatistics(): HeapInfo
Returns an object with the following properties: `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_global_handles_size` The value of total\_global\_handles\_size is the total memory size of V8 global handles. `used_global_handles_size` The value of used\_global\_handles\_size is the used memory size of V8 global handles. `external_memory` The value of external\_memory is the memory size of array buffers and external strings. ```js { 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, total_global_handles_size: 8192, used_global_handles_size: 3296, external_memory: 318824 } ```

Return Type