Thread deadlock

[FurmigaHumana]

Im opening this on Discussions because I dont know if its an issue that can be fixed given the blocking nature of the Socket itself, but maybe it should be documented?

I recently upgraded from 3.2.3 (which started banning the number when reading the qrcode) to 3.5.1 and on my computer with a single number everything worked fine, but as soon as I uploaded to a VPS that I have with 6 numbers it didnt work. I connect to the numbers in sequence with a delay between them, the first number connected fine, but as soon as the second connected they all get stuck, no stacktraces or anything, I would just get a socket OPEN event and some time later a CLOSE event with no other information.

I noticed all threads being stuck in the same place, so I increase the available cores from 4 to 8 (using -XX:ActiveProcessorCount=8) and it improved, but after some time they all got stuck again.

Now I setup a cached thread pool, overriding the shutdownNow() because it is called when the socket closes, I saw peaks of 10 active threads for 6 numbers mostly in idle. It appears it requires quite a few available threads to work, specialy since the CompletableFuture still uses the common pool even when provided with an executor.

`
private static final ThreadPoolExecutor WHATSAPP_EXECUTOR;

static {

    ThreadCounter factory = new ThreadCounter("WhatsApp Thread", true, Thread.NORM_PRIORITY);

    WHATSAPP_EXECUTOR = new ThreadPoolExecutor(
            0, 64,
            5, TimeUnit.MINUTES,
            new SynchronousQueue<>(),
            factory) {
                @Override
                public List<Runnable> shutdownNow() {
                    return null;
                }
          };
}`

Thread dump

threads-1690653410405.txt

[Auties00]

Im opening this on Discussions because I dont know if its an issue that can be fixed given the blocking nature of the Socket itself, but maybe it should be documented?

I recently upgraded from 3.2.3 (which started banning the number when reading the qrcode) to 3.5.1 and on my computer with a single number everything worked fine, but as soon as I uploaded to a VPS that I have with 6 numbers it didnt work. I connect to the numbers in sequence with a delay between them, the first number connected fine, but as soon as the second connected they all get stuck, no stacktraces or anything, I would just get a socket OPEN event and some time later a CLOSE event with no other information.

I noticed all threads being stuck in the same place, so I increase the available cores from 4 to 8 (using -XX:ActiveProcessorCount=8) and it improved, but after some time they all got stuck again.

Now I setup a cached thread pool, overriding the shutdownNow() because it is called when the socket closes, I saw peaks of 10 active threads for 6 numbers mostly in idle. It appears it requires quite a few available threads to work, specialy since the CompletableFuture still uses the common pool even when provided with an executor.

` private static final ThreadPoolExecutor WHATSAPP_EXECUTOR;

static {

    ThreadCounter factory = new ThreadCounter("WhatsApp Thread", true, Thread.NORM_PRIORITY);

    WHATSAPP_EXECUTOR = new ThreadPoolExecutor(
            0, 64,
            5, TimeUnit.MINUTES,
            new SynchronousQueue<>(),
            factory) {
                @Override
                public List<Runnable> shutdownNow() {
                    return null;
                }
          };
}`

Thread dump

threads-1690653410405.txt

Can't you just use a different thread here?

Cobalt/src/main/java/it/auties/whatsapp/api/OptionsBuilder.java

Line 114 in d128d9a

public T socketExecutor(@NonNull Executor socketExecutor) {

This should make it work