Dispatcher.readyAsyncCalls is unbounded, which may cause OOM

[sifei-wang]

It seems that there's no way to control the max size of Dispatcher.readyAsyncCalls.

Consider the following scenario:

1. HTTP server hangs (or unable to respond quickly);
2. Use okhttp to send a large amount of HTTP async requests to the above server;
3. Outgoing requests are stored in Dispatcher.runningAsyncCalls and wait for response/timeout, which means the throughput is very low;
4. Other requests are kept in Dispatcher.readyAsyncCalls, without timeout or limitation of max count. If we keep sending requests, the memory usage of Dispatcher.readyAsyncCalls keeps growing.

[swankjesse]

Unsure what action we should take here. Maybe offer a max size on the queue?

[sifei-wang]

Unsure what action we should take here. Maybe offer a max size on the queue?

Yes, offer a max size on Dispatcher.readyAsyncCalls, or add some timeout mechanism for requests stay at Dispatcher.readyAsyncCalls, either should work.

[MagicWang0907]

You can customize the thread pool, set the maximum number of requests to the maximum integer, and use the blocking queue instead of the ready queue.