1. A small fix of Windows VM size.

third_party/tcmalloc/chromium/src/pagemap.h

 // Copyright (c) 2005, Google Inc.
 // 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
@@ skipping 148 matching lines @@
     committed_[page_num >> 3] |= (1 << (page_num & 0x7));
   }
 
  public:
   typedef uintptr_t Number;
 
   explicit TCMalloc_PageMap1_LazyCommit(void* (*allocator)(size_t)) {
     // TODO(jar): We need a reservation function, but current API to this class
     // only provides an allocator.
     // Get decommitted memory.  We will commit as necessary.
+    size_t size = sizeof(*array_) << BITS;
     array_ = reinterpret_cast<void**>(VirtualAlloc(
-        NULL, sizeof(*array_) << BITS, MEM_RESERVE, PAGE_READWRITE));
+        NULL, size, MEM_RESERVE, PAGE_READWRITE));
+    tcmalloc::update_metadata_system_bytes(size);
+    tcmalloc::update_metadata_unmapped_bytes(size);
 
     // Make sure we divided LENGTH evenly.
     ASSERT(sizeof(committed_) * 8 == (LENGTH * sizeof(*array_)) >> kPageShift);
     // Indicate that none of the pages of array_ have been committed yet.
     memset(committed_, 0, sizeof(committed_));
   }
 
   // Ensure that the map contains initialized and committed entries in array_ to
   // describe pages "x .. x+n-1".
   // Returns true if successful, false if we could not ensure this.
@@ skipping 67 matching lines @@
 #ifndef NDEBUG
     // Validate we are committing new sections, and hence we're not clearing any
     // existing data.
     MEMORY_BASIC_INFORMATION info = {0};
     size_t result = VirtualQuery(start, &info, sizeof(info));
     ASSERT(result);
     ASSERT(0 == (info.State & MEM_COMMIT));  // It starts with uncommitted.
     ASSERT(info.RegionSize >= length);       // Entire length is uncommitted.
 #endif
 
-    // TODO(jar): We need a commit that automatically tallies metadata_bytes.
     TCMalloc_SystemCommit(start, length);
-    tcmalloc::increment_metadata_system_bytes(length);
+    tcmalloc::update_metadata_unmapped_bytes(-length);
 
 #ifndef NDEBUG
     result = VirtualQuery(start, &info, sizeof(info));
     ASSERT(result);
     ASSERT(0 != (info.State & MEM_COMMIT));  // Now it is committed.
     ASSERT(info.RegionSize >= length);       // Entire length is committed.
 #endif
 
     // As noted in the large comment/example describing this method, we will
     // never be called with a range of pages very much inside this |first_page|
@@ skipping 244 matching lines @@
         }
         // Advance to next interior entry
         k = ((k >> LEAF_BITS) + 1) << LEAF_BITS;
       }
     }
     return NULL;
   }
 };
 
 #endif  // TCMALLOC_PAGEMAP_H_