Index: source/lib/allocators/arena.h
===================================================================
--- source/lib/allocators/arena.h   (revision 13914)
+++ source/lib/allocators/arena.h   (working copy)
@@ -1,4 +1,4 @@
-/* Copyright (c) 2010 Wildfire Games
+/* Copyright (c) 2013 Wildfire Games
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
@@ -83,6 +83,88 @@

 LIB_API void TestArena();

+
+/**
+ * allocator design parameters:
+ * - grow dynamically with a fixed chunkSize
+ * - for frequent allocations of size << chunkSize
+ * - no reallocations, pointers remain valid
+ **/
+class DynamicArena
+{
+   struct ArenaChunk
+   {
+       bool Available(size_t size)
+       {
+           return size <= (capacity - end);
+       }
+
+       uintptr_t Allocate(size_t size)
+       {
+           if (!Available(size))
+               return 0;
+           uintptr_t ptr = storage + end;
+           end += size;
+           return ptr;
+       }
+
+       uintptr_t storage;
+       size_t end;
+       size_t capacity;
+       ArenaChunk* next;
+   };
+
+   NONCOPYABLE(DynamicArena);
+public:
+   DynamicArena(size_t chunkSize) : chunkSize(chunkSize), head(NULL)
+   {
+   }
+
+   ~DynamicArena()
+   {
+       ArenaChunk* chunk = head;
+       while (chunk != NULL)
+       {
+           ArenaChunk* next = chunk->next;
+           free(chunk);
+           chunk = next;
+       }
+   }
+
+   void* allocate(size_t size)
+   {
+       if (size > chunkSize)
+       {
+           debug_warn(L"DynamicArena cannot allocate more than chunk size");
+           throw std::bad_alloc();
+       }
+       else if (!head || !head->Available(size))
+       {
+           // For efficiency, do a single allocation with the ArenaChunk and its storage
+           ArenaChunk* oldHead = head;
+           head = (ArenaChunk*)malloc(sizeof(ArenaChunk) + chunkSize);
+           ENSURE(head);
+           head->storage = sizeof(ArenaChunk) + uintptr_t(head);
+           head->end = 0;
+           head->capacity = chunkSize;
+           head->next = oldHead;
+       }
+
+       return (void*)head->Allocate(size);
+   }
+
+   void deallocate(void* UNUSED(p), size_t UNUSED(size))
+   {
+       // ignored
+   }
+
+private:
+
+   const size_t chunkSize;
+   ArenaChunk *head;
+};
+
+
 }  // namespace Allocators

 #endif // #ifndef INCLUDED_ALLOCATORS_ARENA
Index: source/simulation2/serialization/BinarySerializer.cpp
===================================================================
--- source/simulation2/serialization/BinarySerializer.cpp   (revision 13914)
+++ source/simulation2/serialization/BinarySerializer.cpp   (working copy)
@@ -57,7 +57,7 @@

 CBinarySerializerScriptImpl::CBinarySerializerScriptImpl(ScriptInterface& scriptInterface, ISerializer& serializer) :
    m_ScriptInterface(scriptInterface), m_Serializer(serializer), m_Rooter(m_ScriptInterface),
-   m_ScriptBackrefsArena(16*MiB), m_ScriptBackrefs(backrefs_t::key_compare(), ScriptBackrefsAlloc(m_ScriptBackrefsArena)), m_ScriptBackrefsNext(1)
+   m_ScriptBackrefsArena(1 * MiB), m_ScriptBackrefs(backrefs_t::key_compare(), ScriptBackrefsAlloc(m_ScriptBackrefsArena)), m_ScriptBackrefsNext(1)
 {
 }

Index: source/simulation2/serialization/BinarySerializer.h
===================================================================
--- source/simulation2/serialization/BinarySerializer.h (revision 13914)
+++ source/simulation2/serialization/BinarySerializer.h (working copy)
@@ -65,10 +65,10 @@
    ISerializer& m_Serializer;

    // Pooling helps since we do a lot of short-lived allocations
-   typedef ProxyAllocator<std::pair<JSObject* const, u32>, Allocators::Arena<> > ScriptBackrefsAlloc;
+   typedef ProxyAllocator<std::pair<JSObject* const, u32>, Allocators::DynamicArena> ScriptBackrefsAlloc;
    typedef std::map<JSObject*, u32, std::less<JSObject*>, ScriptBackrefsAlloc> backrefs_t;

-   Allocators::Arena<> m_ScriptBackrefsArena;
+   Allocators::DynamicArena m_ScriptBackrefsArena;
    backrefs_t m_ScriptBackrefs;
    u32 m_ScriptBackrefsNext;
    u32 GetScriptBackrefTag(JSObject* obj);