lib/v8.js

   1 // Copyright (c) 2014, StrongLoop Inc.
   2 //
   3 // Permission to use, copy, modify, and/or distribute this software for any
   4 // purpose with or without fee is hereby granted, provided that the above
   5 // copyright notice and this permission notice appear in all copies.
   6 //
   7 // THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   8 // WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   9 // MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  10 // ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  11 // WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  12 // ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  13 // OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  14
  15 'use strict';
  16
  17 const v8binding = process.binding('v8');
  18
  19 const heapStatisticsBuffer =
  20     new Uint32Array(v8binding.heapStatisticsArrayBuffer);
  21
  22 const kTotalHeapSizeIndex = v8binding.kTotalHeapSizeIndex;
  23 const kTotalHeapSizeExecutableIndex = v8binding.kTotalHeapSizeExecutableIndex;
  24 const kTotalPhysicalSizeIndex = v8binding.kTotalPhysicalSizeIndex;
  25 const kTotalAvailableSize = v8binding.kTotalAvailableSize;
  26 const kUsedHeapSizeIndex = v8binding.kUsedHeapSizeIndex;
  27 const kHeapSizeLimitIndex = v8binding.kHeapSizeLimitIndex;
  28
  29 exports.getHeapStatistics = function() {
  30   const buffer = heapStatisticsBuffer;
  31
  32   v8binding.updateHeapStatisticsArrayBuffer();
  33
  34   return {
  35     'total_heap_size': buffer[kTotalHeapSizeIndex],
  36     'total_heap_size_executable': buffer[kTotalHeapSizeExecutableIndex],
  37     'total_physical_size': buffer[kTotalPhysicalSizeIndex],
  38     'total_available_size': buffer[kTotalAvailableSize],
  39     'used_heap_size': buffer[kUsedHeapSizeIndex],
  40     'heap_size_limit': buffer[kHeapSizeLimitIndex]
  41   };
  42 };
  43
  44 exports.setFlagsFromString = v8binding.setFlagsFromString;