Recursive process.nextTick warning

Question

As part of my app, I have the following lines of code:

process.nextTick(function() {
  // pre-populate cache with all users
  console.log('scanning users table in order to pre-populate cache');
  tables.users.scan(function(err, users) {
    if (err) {
      console.error('unable to scan users database in order to pre-populate cache');
      return;
    }

    console.log('found %d users in database', users.length);
  });
});

running the app in ubuntu gives me

(node) warning: Recursive process.nextTick detected. This will break in the next version of node. Please use setImmediate for recursive deferral.

RangeError: Maximum call stack size exceeded

running on OSX is working good no warnings at all.

Both run the same node version v0.10.24.

Removing this block of code solves the problem. I am trying to figure out what's going on here.

Trying to run node with --trace-deprecation flag shows

Trace: (node) warning: Recursive process.nextTick detected. This will break in the next version of node. Please use setImmediate for recursive deferral.
    at maxTickWarn (node.js:377:17)
    at process.nextTick (node.js:480:9)
    at onwrite (_stream_writable.js:260:15)
    at WritableState.onwrite (_stream_writable.js:97:5)
    at WriteStream.Socket._write (net.js:651:5)
    at doWrite (_stream_writable.js:221:10)
    at writeOrBuffer (_stream_writable.js:211:5)
    at WriteStream.Writable.write (_stream_writable.js:180:11)
    at WriteStream.Socket.write (net.js:613:40)
    at Console.warn (console.js:61:16)
    at Console.trace (console.js:95:8)
    at maxTickWarn (node.js:377:17)

running with --throw-deprecation gives

Error: (node) warning: Recursive process.nextTick detected. This will break in the next version of node. Please use setImmediate for recursive deferral.
    at maxTickWarn (node.js:375:15)
    at process.nextTick (node.js:480:9)
    at Cursor.each (/var/www/node_modules/mongojs/node_modules/mongodb/lib/mongodb/cursor.js:184:13)
    at /var/www/node_modules/mongojs/node_modules/mongodb/lib/mongodb/cursor.js:191:16
    at Cursor.nextObject (/var/www/node_modules/mongojs/node_modules/mongodb/lib/mongodb/cursor.js:540:5)
    at /var/www/node_modules/mongojs/node_modules/mongodb/lib/mongodb/cursor.js:187:12
    at process._tickCallback (node.js:415:13)

Any help much appreciated.

10x

Answer 1

It turns out the problem was in one of the modules I used in my app - mongojs. The problem was solved in a later version of the module, I just needed to update my package.json.

Jamis Charles comment about running my app with node --throw-deprecation app.js (or --trace-deprecation) showed me the stack trace of the error that led me to the culprit module.

I'm still not sure why the problem showed in Ubuntu and not on my MBA...