Node.js Buffer用法解读

清空buffer数据最快的办法是buffer.fill(0)

buffer模块与Buffer的关系

Buffer是全局global上的一个引用，指向的其实是buffer.Buffer

 const buffer = require('buffer');
 console.log(buffer.Buffer === Buffer); //true

buffer模块上还有其他一些属性和方法

const buffer = require('buffer');
console.log(buffer);
{ Buffer:
  { [Function: Buffer]   poolSize: 8192,
   from: [Function: from],
   alloc: [Function: alloc],
   allocUnsafe: [Function: allocUnsafe],
   allocUnsafeSlow: [Function: allocUnsafeSlow],
   isBuffer: [Function: isBuffer],
   compare: [Function: compare],
   isEncoding: [Function: isEncoding],
   concat: [Function: concat],
   byteLength: [Function: byteLength],
   [Symbol(node.isEncoding)]: [Function: isEncoding] },
 SlowBuffer: [Function: SlowBuffer],
 transcode: [Function: transcode],
 INSPECT_MAX_BYTES: 50,
 kMaxLength: 2147483647,
 kStringMaxLength: 1073741799,
 constants: { MAX_LENGTH: 2147483647, MAX_STRING_LENGTH: 1073741799 } }

上面的kMaxLength与MAX_LENGTH代表了新建buffer时内存大小的最大值，当超过限制值后就会报错

32为机器上是(2^30)-1(~1GB)

64位机器上是(2^31)-1(~2GB)

Buffer释放

我们无法手动对buffer实例进行GC，只能依靠V8来进行，我们唯一能做的就是解除对buffer实例的引用

参考资料

http://cenalulu.github.io/linux/character-encoding/
//www.jb51.net/article/31045.htm
http://edu.jb51.net/nodejs/nodejs-buffer.html