function ResourceCacheStatistics() {
  /**
   * The size of vertex buffers and index buffers loaded in the cache in bytes.
   *
   * @type {number}
   * @private
   */
  this.geometryByteLength = 0;

  /**
   * The size of all textures loaded in the cache in bytes
   *
   * @type {number}
   * @private
   */
  this.texturesByteLength = 0;

  // Track the sizes of resources by cache key. This is important so
  // removeLoader() can decrement the counts correctly.
  this._geometrySizes = {};
  this._textureSizes = {};
}
Statistics for the GPU and CPU memory used by the models loaded through the
{@link ResourceCache}.

@alias ResourceCacheStatistics
@constructor

@private