Bug 1770768 - Part 3: Add browser prefs for the new GC parameters r=mccr8,sfink

Differential Revision: https://phabricator.services.mozilla.com/D152864

dom/base/nsJSEnvironment.cpp

@@ -2073,6 +2073,16 @@ void nsJSContext::EnsureStatics() {
       "javascript.options.mem.gc_high_frequency_small_heap_growth",
       (void*)JSGC_HIGH_FREQUENCY_SMALL_HEAP_GROWTH);
 
+  Preferences::RegisterCallbackAndCall(
+      SetMemoryPrefChangedCallbackBool,
+      "javascript.options.mem.gc_balanced_heap_limits",
+      (void*)JSGC_BALANCED_HEAP_LIMITS_ENABLED);
+
+  Preferences::RegisterCallbackAndCall(
+      SetMemoryPrefChangedCallbackInt,
+      "javascript.options.mem.gc_heap_growth_factor",
+      (void*)JSGC_HEAP_GROWTH_FACTOR);
+
   Preferences::RegisterCallbackAndCall(
       SetMemoryPrefChangedCallbackInt,
       "javascript.options.mem.gc_small_heap_size_max_mb",

dom/workers/RuntimeService.cpp

@@ -350,6 +350,8 @@ void LoadJSGCMemoryOptions(const char* aPrefName, void* /* aClosure */) {
            JSGC_HIGH_FREQUENCY_SMALL_HEAP_GROWTH),
       PREF("gc_small_heap_size_max_mb", JSGC_SMALL_HEAP_SIZE_MAX),
       PREF("gc_large_heap_size_min_mb", JSGC_LARGE_HEAP_SIZE_MIN),
+      PREF("gc_balanced_heap_limits", JSGC_BALANCED_HEAP_LIMITS_ENABLED),
+      PREF("gc_heap_growth_factor", JSGC_HEAP_GROWTH_FACTOR),
       PREF("gc_allocation_threshold_mb", JSGC_ALLOCATION_THRESHOLD),
       PREF("gc_malloc_threshold_base_mb", JSGC_MALLOC_THRESHOLD_BASE),
       PREF("gc_small_heap_incremental_limit",
@@ -408,7 +410,8 @@ void LoadJSGCMemoryOptions(const char* aPrefName, void* /* aClosure */) {
         UpdateOtherJSGCMemoryOption(rts, pref->key, value);
         break;
       }
-      case JSGC_COMPACTING_ENABLED: {
+      case JSGC_COMPACTING_ENABLED:
+      case JSGC_BALANCED_HEAP_LIMITS_ENABLED: {
         bool present;
         bool prefValue = GetPref(pref->fullName, false, &present);
         Maybe<uint32_t> value = present ? Some(prefValue ? 1 : 0) : Nothing();
@@ -428,6 +431,7 @@ void LoadJSGCMemoryOptions(const char* aPrefName, void* /* aClosure */) {
       case JSGC_URGENT_THRESHOLD_MB:
       case JSGC_MIN_EMPTY_CHUNK_COUNT:
       case JSGC_MAX_EMPTY_CHUNK_COUNT:
+      case JSGC_HEAP_GROWTH_FACTOR:
         UpdateCommonJSGCMemoryOption(rts, pref->fullName, pref->key);
         break;
       default:

js/public/GCAPI.h

@@ -229,6 +229,7 @@ typedef enum JSGCParamKey {
    * Otherwise, heap limits are set based on a linear multiple of the retained
    * size after the last collection.
    *
+   * Pref: javascript.options.mem.gc_balanced_heap_limits
    * Default: BalancedHeapLimitsEnabled
    */
   JSGC_BALANCED_HEAP_LIMITS_ENABLED = 17,
@@ -239,6 +240,7 @@ typedef enum JSGCParamKey {
    * This parameter trades off GC time for memory usage. Smaller values result
    * in lower memory use and larger values result in less time spent collecting.
    *
+   * Pref: javascript.options.mem.gc_heap_growth_factor
    * Default: HeapGrowthFactor
    */
   JSGC_HEAP_GROWTH_FACTOR = 18,

modules/libpref/init/all.js

@@ -1042,6 +1042,12 @@ pref("javascript.options.mem.gc_high_frequency_large_heap_growth", 150);
 // JSGC_LOW_FREQUENCY_HEAP_GROWTH
 pref("javascript.options.mem.gc_low_frequency_heap_growth", 150);
 
+// JSGC_BALANCED_HEAP_LIMITS_ENABLED
+pref("javascript.options.mem.gc_balanced_heap_limits", false);
+
+// JSGC_HEAP_GROWTH_FACTOR
+pref("javascript.options.mem.gc_heap_growth_factor", 40);
+
 // JSGC_ALLOCATION_THRESHOLD
 pref("javascript.options.mem.gc_allocation_threshold_mb", 27);