v8: export more fields in getHeapStatistics

export total_global_handles_size, used_global_handles_size,
external_memory in getHeapStatistics

Author: theanarkh

doc/api/v8.md

@@ -180,6 +180,9 @@ Returns an object with the following properties:
 * `does_zap_garbage` {number}
 * `number_of_native_contexts` {number}
 * `number_of_detached_contexts` {number}
+* `total_global_handles_size` {number}
+* `used_global_handles_size` {number}
+* `external_memory` {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
@@ -195,6 +198,15 @@ a memory leak.
 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.
+
 <!-- eslint-skip -->
 
 ```js
@@ -209,7 +221,10 @@ being non-zero indicates a potential memory leak.
   peak_malloced_memory: 1127496,
   does_zap_garbage: 0,
   number_of_native_contexts: 1,
-  number_of_detached_contexts: 0
+  number_of_detached_contexts: 0,
+  total_global_handles_size: 8192,
+  used_global_handles_size: 3296,
+  external_memory: 318824
 }
 ```
 

lib/v8.js

@@ -107,6 +107,9 @@ const {
   kPeakMallocedMemoryIndex,
   kNumberOfNativeContextsIndex,
   kNumberOfDetachedContextsIndex,
+  kTotalGlobalHandlesSizeIndex,
+  kUsedGlobalHandlesSizeIndex,
+  kExternalMemoryIndex,
 
   // Properties for heap spaces statistics buffer extraction.
   kHeapSpaces,
@@ -165,7 +168,10 @@ function getHeapStatistics() {
     peak_malloced_memory: buffer[kPeakMallocedMemoryIndex],
     does_zap_garbage: buffer[kDoesZapGarbageIndex],
     number_of_native_contexts: buffer[kNumberOfNativeContextsIndex],
-    number_of_detached_contexts: buffer[kNumberOfDetachedContextsIndex]
+    number_of_detached_contexts: buffer[kNumberOfDetachedContextsIndex],
+    total_global_handles_size: buffer[kTotalGlobalHandlesSizeIndex],
+    used_global_handles_size: buffer[kUsedGlobalHandlesSizeIndex],
+    external_memory: buffer[kExternalMemoryIndex]
   };
 }
 

src/node_v8.cc

@@ -59,7 +59,10 @@ using v8::Value;
   V(7, peak_malloced_memory, kPeakMallocedMemoryIndex)                        \
   V(8, does_zap_garbage, kDoesZapGarbageIndex)                                \
   V(9, number_of_native_contexts, kNumberOfNativeContextsIndex)               \
-  V(10, number_of_detached_contexts, kNumberOfDetachedContextsIndex)
+  V(10, number_of_detached_contexts, kNumberOfDetachedContextsIndex)          \
+  V(11, total_global_handles_size, kTotalGlobalHandlesSizeIndex)              \
+  V(12, used_global_handles_size, kUsedGlobalHandlesSizeIndex)                \
+  V(13, external_memory, kExternalMemoryIndex)
 
 #define V(a, b, c) +1
 static constexpr size_t kHeapStatisticsPropertiesCount =

test/parallel/test-v8-stats.js

@@ -6,15 +6,18 @@ const v8 = require('v8');
 const s = v8.getHeapStatistics();
 const keys = [
   'does_zap_garbage',
+  'external_memory',
   'heap_size_limit',
   'malloced_memory',
   'number_of_detached_contexts',
   'number_of_native_contexts',
   'peak_malloced_memory',
   'total_available_size',
+  'total_global_handles_size',
   'total_heap_size',
   'total_heap_size_executable',
   'total_physical_size',
+  'used_global_handles_size',
   'used_heap_size'];
 assert.deepStrictEqual(Object.keys(s).sort(), keys);
 keys.forEach(function(key) {