longStackTraces memory issue

[Volox]

Hi,
i have a memory issue using Promise.longStackTraces(). I tried to create an "infite loop" for a crawler and noticed a huge memory usage for the application; i debugged the application and found a strange behaviour.

The following code illustrates the problem:

var Promise = require( 'bluebird' );
Promise.longStackTraces();
var SIZE=1024*1024;

function crawlLoop() {
  var arr = [];
  for( var i=0; i<SIZE; i++ ) {
    arr.push( {} );
  }
  return Promise.resolve( arr ).then( crawlLoop );
}

crawlLoop();

After a few tentatives i noticed that by removing Promise.longStackTraces() the problem was solved.
Another solution is to call setImmediate in the last then of the promise like:

return Promise.resolve( arr ).then( function() { setImmediate( crawlLoop ); } );

Can someone please explain me what is wrong with the code (a part for the infinite loop)?

My configuration:
node x64 0.11.13
Windows x64
Bluebird: 2.3.11

Thanks!

[petkaantonov]

Can you use the latest version? The memory leak was fixed in 2.4.3 (But don't use that exact version, as it caused several regressions which were later fixed)

[janez87]

Hi,
I can reproduce the problem with the latest (2.6.4) version.

node x64 0.10.28
osx 10.10

[Volox]

Just updated to 2.6.4 still same problem :(

[petkaantonov]

I can fix the memory leak but the given code will still keep using maximum memory because it runs synchronously. However if you do someAsyncAction().then(crawlLoop) there is no memory issue. Is such fix fine?

[Volox]

I've got the same problem also using an async function like in the following code:

var Promise = require( 'bluebird' );
Promise.longStackTraces();

var SIZE=1024*1024;

var asyncFun = function() {
  return new Promise( function( res ) {
    setTimeout( function() {
      var arr = [];
      for( var i=0; i<SIZE; i++ ) {
        arr.push( {} );
      }
      return res( arr );
    }, 100 );
  } );
};

function crawlLoop() {
  return asyncFun()
  .then( crawlLoop );
  // .then( function() { setImmediate( crawlLoop ); } );
}

crawlLoop();

[petkaantonov]

Fixed in 2.7.1, the original code stays at 100MB working set

[Volox]

Thanks!