code: function _free(meminfo, units) {
    units = units || 'bytes';
  
    var freeMem = meminfo.memFree;
    var cached = meminfo.cached;
    var buffers = meminfo.buffers;
  
    var totalFreeMem = freeMem + cached + buffers;
    var totalFreeMemBytes = totalFreeMem * 1024;
    var converted = _bytesTo(totalFreeMemBytes, units);
  
    return converted;
  }
docs: /* PRIVATE