performance-nodejs

performance-nodejs

Get nodejs performance, such as: heap statistics, event loop delay

Installation

$ npm i performance-nodejs

Examples

View the ./examples directory for working examples.

Description

The performance() function get node.js performance (include event loop, heap statistics and heap space statistics).

• If node.js support v8.getHeapSpaceStatistics(), the heap space will be return.

const timer = performance(fn, interval);

• fn: The callback function to execute.

• interval: Check interval, defaulted to 100ms.

• unit: Set the heap format unit, eg: 'B', 'MB', 'GB', '0.0MB' defaulted to 'B'. 0.00MB means set 2 precision and 'MB' unit.

Returns: A reference to the timer. Useful for clearing the timer.

cpuUsage is new in node.js v6.x.

malloced_memory, peak_malloced_memory and does_zap_garbage is new in node.js v7.x

// node.js performance
{
  "lag": 0,
  "heap": {
    "total_heap_size": 7,
    "total_heap_size_executable": 5,
    "total_physical_size": 7,
    "total_available_size": 1421,
    "used_heap_size": 3,
    "heap_size_limit": 1432,
    "malloced_memory": 0,
    "peak_malloced_memory": 1,
    "does_zap_garbage": 0
  },
  "heapSpace": {
    "new_space": {
      "size": 2,
      "used_size": 1,
      "available_size": 0,
      "physical_size": 2
    },
    "old_space": {
      "size": 2,
      "used_size": 1,
      "available_size": 0,
      "physical_size": 2
    },
    "code_space": {
      "size": 2,
      "used_size": 1,
      "available_size": 0,
      "physical_size": 2
    },
    "map_space": {
      "size": 1,
      "used_size": 0,
      "available_size": 0,
      "physical_size": 1
    },
    "large_object_space": {
      "size": 0,
      "used_size": 0,
      "available_size": 1421,
      "physical_size": 0
    }
  },
  "cpuUsage": {
    "user": 1966,
    "system": 185,
    "usedPercent": 1,
    "total": 474737
  }
}

performance(data => {
	console.info(JSON.stringify(data));
}, 'MB', 100);

License

MIT