Grow old generation slower on low-memory devices.

src/api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 442 matching lines @@
                      (source ? static_cast<int>(strlen(source)) : 0)),
       source_(source, source_length_),
       dep_count_(dep_count),
       deps_(deps),
       auto_enable_(false) {
   CHECK(source != NULL || source_length_ == 0);
 }
 
 
 ResourceConstraints::ResourceConstraints()
-    : max_young_space_size_(0),
+    : max_new_space_size_(0),
       max_old_space_size_(0),
       max_executable_size_(0),
       stack_limit_(NULL),
       max_available_threads_(0),
       code_range_size_(0) { }
 
 void ResourceConstraints::ConfigureDefaults(uint64_t physical_memory,
                                             uint64_t virtual_memory_limit,
                                             uint32_t number_of_processors) {
   const int lump_of_memory = (i::kPointerSize / 4) * i::MB;

[rmcilroy, 2014/04/16 08:28:15]

nit - if you move lump_of_memory, to heap.h too, then the sizes could be simply
in MB (and the growth factor check would match the heap size even on 64bit
device).

[Hannes Payer (out of office), 2014/04/17 10:30:04]

Done.

 #if V8_OS_ANDROID
   // Android has higher physical memory requirements before raising the maximum
   // heap size limits since it has no swap space.
   const uint64_t low_limit = 512ul * i::MB;
   const uint64_t medium_limit = 1ul * i::GB;
   const uint64_t high_limit = 2ul * i::GB;
 #else
   const uint64_t low_limit = 512ul * i::MB;
   const uint64_t medium_limit = 768ul * i::MB;
   const uint64_t high_limit = 1ul  * i::GB;
 #endif
 
-  // The young_space_size should be a power of 2 and old_generation_size should
-  // be a multiple of Page::kPageSize.
   if (physical_memory <= low_limit) {
-    set_max_young_space_size(2 * lump_of_memory);
-    set_max_old_space_size(128 * lump_of_memory);
-    set_max_executable_size(96 * lump_of_memory);
+    set_max_new_space_size(
+        i::Heap::kMaxNewSpaceSizeLowMemoryDevice * lump_of_memory);
+    set_max_old_space_size(
+        i::Heap::kMaxOldSpaceSizeLowMemoryDevice * lump_of_memory);
+    set_max_executable_size(
+        i::Heap::kMaxExecutableSizeLowMemoryDevice * lump_of_memory);
   } else if (physical_memory <= medium_limit) {
-    set_max_young_space_size(8 * lump_of_memory);
-    set_max_old_space_size(256 * lump_of_memory);
-    set_max_executable_size(192 * lump_of_memory);
+    set_max_new_space_size(
+        i::Heap::kMaxNewSpaceSizeMediumMemoryDevice * lump_of_memory);
+    set_max_old_space_size(
+        i::Heap::kMaxOldSpaceSizeMediumMemoryDevice * lump_of_memory);
+    set_max_executable_size(
+        i::Heap::kMaxExecutableSizeMediumMemoryDevice * lump_of_memory);
   } else if (physical_memory <= high_limit) {
-    set_max_young_space_size(16 * lump_of_memory);
-    set_max_old_space_size(512 * lump_of_memory);
-    set_max_executable_size(256 * lump_of_memory);
+    set_max_new_space_size(
+        i::Heap::kMaxNewSpaceSizeHighMemoryDevice * lump_of_memory);
+    set_max_old_space_size(
+        i::Heap::kMaxOldSpaceSizeHighMemoryDevice * lump_of_memory);
+    set_max_executable_size(
+        i::Heap::kMaxExecutableSizeHighMemoryDevice * lump_of_memory);
   } else {
-    set_max_young_space_size(16 * lump_of_memory);
-    set_max_old_space_size(700 * lump_of_memory);
-    set_max_executable_size(256 * lump_of_memory);
+    set_max_new_space_size(
+        i::Heap::kMaxNewSpaceSizeHugeMemoryDevice * lump_of_memory);
+    set_max_old_space_size(
+        i::Heap::kMaxOldSpaceSizeHugeMemoryDevice * lump_of_memory);
+    set_max_executable_size(
+        i::Heap::kMaxExecutableSizeHugeMemoryDevice * lump_of_memory);
   }
 
   set_max_available_threads(i::Max(i::Min(number_of_processors, 4u), 1u));
 
   if (virtual_memory_limit > 0 && i::kIs64BitArch) {
     // Reserve no more than 1/8 of the memory for the code range, but at most
     // 512 MB.
     set_code_range_size(
         i::Min(512 * i::MB, static_cast<int>(virtual_memory_limit >> 3)));
   }
 }
 
 
 bool SetResourceConstraints(Isolate* v8_isolate,
                             ResourceConstraints* constraints) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(v8_isolate);
-  int young_space_size = constraints->max_young_space_size();
+  int new_space_size = constraints->max_new_space_size();
   int old_gen_size = constraints->max_old_space_size();
   int max_executable_size = constraints->max_executable_size();
   int code_range_size = constraints->code_range_size();
-  if (young_space_size != 0 || old_gen_size != 0 || max_executable_size != 0 ||
+  if (new_space_size != 0 || old_gen_size != 0 || max_executable_size != 0 ||
       code_range_size != 0) {
     // After initialization it's too late to change Heap constraints.
     ASSERT(!isolate->IsInitialized());
-    bool result = isolate->heap()->ConfigureHeap(young_space_size / 2,
+    bool result = isolate->heap()->ConfigureHeap(new_space_size / 2,
                                                  old_gen_size,
                                                  max_executable_size,
                                                  code_range_size);
     if (!result) return false;
   }
   if (constraints->stack_limit() != NULL) {
     uintptr_t limit = reinterpret_cast<uintptr_t>(constraints->stack_limit());
     isolate->stack_guard()->SetStackLimit(limit);
   }
 
@@ skipping 7117 matching lines @@
   Isolate* isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 } }  // namespace v8::internal