Ok, I see, thanks Raymond. 

Queue based logging leaks seem to hang my deployed applications atm, so this seemed like a possible reason for it. I use locally 8GB Ubuntu, and it gets to 2.2% after return with 20million puts, and on a remote 1GB Ubuntu instance, it gets to 3.79% up from 1.24% with 3 million puts after return. So I don't think this is necessarily specific to my local build and seems like a genuine issue.

I understand where are you coming from stating that it's not a bug, but the alternative deque implementations don't seem to suffer from the same issue, at least to such a big extent, as I have shown.

I will continue and try to adapt alternate deque implementations and see if it solves Queues leaking and hanging my instances.

Thanks for your time and involvement in this.