Possible memory leak when calling uv_queue_work from an addon multiple times

[oferh]

I've created a minimal asynchronous addon based on NAN example async_pi_estimate and ran it in a loop. It appears that there is a memory leak when using it because the code itself doesn't allocate
dynamic memory but after ~15 sec it crashes with:

FATAL ERROR:CALL_AND_RETRY_LAST Allocation failed - process out of memory

Also tried running twice with 2K iterations the memory footprint is as follows:

This is the output after the first round:

==28951== LEAK SUMMARY:
==28951==    definitely lost: 288 bytes in 1 blocks
==28951==    indirectly lost: 0 bytes in 0 blocks
==28951==      possibly lost: 7,241 bytes in 51 blocks
==28951==    still reachable: 1,084,994 bytes in 222 blocks
==28951==         suppressed: 0 bytes in 0 blocks

And this is the output after the 2nd one:

==28966== LEAK SUMMARY:
==28966==    definitely lost: 288 bytes in 1 blocks
==28966==    indirectly lost: 0 bytes in 0 blocks
==28966==      possibly lost: 7,241 bytes in 51 blocks
==28966==    still reachable: 1,249,474 bytes in 238 blocks
==28966==         suppressed: 0 bytes in 0 blocks

The code is available in this gist
Node version: 0.12.7

[oferh]

Another report on the same issue without NAN http://stackoverflow.com/questions/33346385/how-can-i-use-uv-queue-work-multiple-times

[bnoordhuis]

Why do you report it here and not at https://github.com/nodejs/nan?

[bnoordhuis]

Also, why are you trying to start one billion asynchronous work items? Small wonder it runs out of memory.

because the code itself doesn't allocate dynamic memory

What do you think this is? From your gist:

  Callback *callback = new Callback(info[0].As<Function>());

  AsyncQueueWorker(new AsyncTestWorker(callback));

I'll close the issue, I don't see a bug here.

[kkoopa]

It was here too: nodejs/nan#501 but there is no reason it would leak from NAN's pov. AsyncQueueWorker deletes the worker after it has been executed, which takes the Callback with it. As far as I could tell, the issue is just that one should not start a billion asynchronous work items.

[oferh]

Thanks @kkoopa and @bnoordhuis, it was my mistake the loop keeps creating new AsyncQueueWorker (threads) without waiting for the previous workers to complete and this of course is the reason for the memory issue.

[bnoordhuis]

No problem. I think you posted to the libuv mailing list earlier this week, didn't you? Maybe you can post a follow-up?

[karimcitoh]

@bnoordhuis I was the one who posted to the libuv mailing list last week. Already posted a follow-up. This is not a bug. As @kkoopa said, AsyncQueueWorker deletes the worker after it has been executed. Thanks for the help!