nodejs require cause memory leak

[xiachaoxulu]

• Version: 4.3.1
• Platform:window 64
• Subsystem:

// test.js **************
var app
app=require('./test1')

setInterval(function() {
delete require.cache[require.resolve('./test1')]
app = require('./test1')
}, 2000)

setInterval(function() {
console.log('==================')
console.log(process.memoryUsage())
console.log('==================')
}, 500)

// test1.js **************

var arr = new Array(40 * 1024 * 1024)
module.exports = {
a: arr
}

Then ,i run the node with the follow command:

node --trace_gc test.js

In console, i get out of memory

[andrasq]

this came up just recently, but can't find the ticket.

The leak is because the module is also cached in the module .parent.children; deleting it from require.cache is not sufficient. Need to

mod = require.cache[path];
delete require.cache[path];
ix = mod.parent.children.indexOf(mod);
if (ix >= 0) mod.parent.children.splice(ix, 1);

[bnoordhuis]

Duplicate of #8443, closing. Thanks for answering, @andrasq.

[xiachaoxulu]

Thanks for answering

[hjain60]

Even with the below added code as suggested by andrasq, there is memory leak.

mod = require.cache[path];
delete require.cache[path];
ix = mod.parent.children.indexOf(mod);
if (ix >= 0) mod.parent.children.splice(ix, 1);

Please see the below example:

while(true) {
  var file = './test1';
  require(file);


  var mod = require.cache[require.resolve(file)];
  if (mod) {
    var ix = mod.parent.children.indexOf(mod);
    if (ix >= 0) {
      mod.parent.children.splice(ix, 1);
    }
  }

  delete require.cache[require.resolve(file)];
}

The above code will leak memory over 1mb/sec. Any pointers on how to make the above code work to not leak memory are greatly appreciated.