Add methods to enable configuration of ResourceConstraints based on limits derived at runtime.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 0a38fa9f32b2b3e3932a178d756c80b44b1a0c1e..36491a4c1b0713102961bece3e235423f638163b 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -633,6 +633,41 @@ bool SetResourceConstraints(ResourceConstraints* constraints) {
 }
 
 
+bool ConfigureResourceConstraintsForCurrentPlatform(

[Hannes Payer (out of office), 2013/09/24 11:27:17]

We could also move the implementation in a separate file. Danno, what do you
think?

[danno, 2013/09/24 11:52:24]

Yes, please put this in another file to make it clear that it's not part of the
core.

+    ResourceConstraints* constraints) {
+  if (constraints == NULL) {
+    return false;
+  }
+
+  // young_space_size should be a power of 2 and old_generation_size should be
+  // a multiple of Page::kPageSize.
+  uintptr_t physical_memory = i::OS::TotalPhysicalMemory();
+  uintptr_t lump_of_memory = i::kIs64BitArch ? 2 * i::MB : i::MB;
+  if (physical_memory > 2ul * i::GB) {
+    constraints->set_max_young_space_size(8 * lump_of_memory);
+    constraints->set_max_old_space_size(700 * lump_of_memory);
+    constraints->set_max_executable_size(256 * lump_of_memory);
+  } else if (physical_memory > 512ul * i::MB) {
+    constraints->set_max_young_space_size(4 * lump_of_memory);
+    constraints->set_max_old_space_size(192 * lump_of_memory);
+    constraints->set_max_executable_size(192 * lump_of_memory);
+  } else /* (physical_memory <= 512GB) */ {
+    constraints->set_max_young_space_size(1 * lump_of_memory);
+    constraints->set_max_old_space_size(96 * lump_of_memory);
+    constraints->set_max_executable_size(96 * lump_of_memory);
+  }
+  return true;
+}
+
+
+bool SetDefaultResourceConstraintsForCurrentPlatform() {
+  ResourceConstraints constraints;
+  if (!ConfigureResourceConstraintsForCurrentPlatform(&constraints))
+    return false;
+  return SetResourceConstraints(&constraints);
+}
+
+
 i::Object** V8::GlobalizeReference(i::Isolate* isolate, i::Object** obj) {
   if (IsDeadCheck(isolate, "V8::Persistent::New")) return NULL;
   LOG_API(isolate, "Persistent::New");