iOS mesh app discarding packets due to sequence number

RE: iOS mesh app discarding packets due to sequence number

Aleksander Nowakowski — Thu, 19 Nov 2020 16:01:57 GMT

You don't need to modify the library. The queue can be given as a parameter in Manager's initializer.

RE: iOS mesh app discarding packets due to sequence number

ftjandra — Thu, 12 Nov 2020 16:05:29 GMT

So it looks like all I need to do is change that line to:

//queue: DispatchQueue = DispatchQueue.global(qos: .background),
queue: DispatchQueue = DispatchQueue(label: "serial"),

RE: iOS mesh app discarding packets due to sequence number

Aleksander Nowakowski — Thu, 12 Nov 2020 15:43:27 GMT

www.avanderlee.com/.../

RE: iOS mesh app discarding packets due to sequence number

ftjandra — Thu, 12 Nov 2020 15:37:48 GMT

For some reason I thought that DispatchQueues were serial by default. How would I modify this to make it a serial queue?

Thanks.

RE: iOS mesh app discarding packets due to sequence number

Aleksander Nowakowski — Thu, 12 Nov 2020 15:32:40 GMT

https://github.com/NordicSemiconductor/IOS-nRF-Mesh-Library/blob/0861ceba2cb13fa0e60960cd3a818efb5b852803/nRFMeshProvision/Classes/MeshNetworkManager.swift#L174

It's still concurrent queue.

RE: iOS mesh app discarding packets due to sequence number

Aleksander Nowakowski — Thu, 12 Nov 2020 15:29:43 GMT

If it indeed uses serial queue, that wasn't intended. I'll look into it.. when I'm back from my leave in mid January.

RE: iOS mesh app discarding packets due to sequence number

Aleksander Nowakowski — Thu, 12 Nov 2020 15:27:02 GMT

This part hasn't changed. You may safely change to serial queue and should see no side effects. All delays are negletable.

Btw, was it difficult for you to migrate? Do you consider 3.0-beta1 API better, in spite of new features?

RE: iOS mesh app discarding packets due to sequence number

ftjandra — Thu, 12 Nov 2020 15:18:32 GMT

Ok, we finally migrated to 3.0-beta1 and the problem is still there. It looks like 3.0-beta1 is already using serial DispatchQueues for the MeshNetworkManager, correct?

Thanks.

RE: iOS mesh app discarding packets due to sequence number

Aleksander Nowakowski — Fri, 09 Oct 2020 04:33:38 GMT

There should be no drawbacks, at least I didn't observe any. It's Dispatch Queue, so should be stable and reliable.

Yes, 3.0 requires some API changes, but they aren't that big. Check out the latest PRs, where is all described. However, only migrating to 3.0 doesn't guarantee that this weird issue you have will be solved. Nevertheless, I recommend as it's better.

RE: iOS mesh app discarding packets due to sequence number

ftjandra — Fri, 09 Oct 2020 01:56:15 GMT

Hi,

We are using 2.2.3. We just tried to use 3.0-beta1, but the app wont build and looks like a lot of things have changed and we will need to do quite a bit of rework. Is there a changelog of the changes?

What is the drawback of using a serial processing queue? Delays? Drops if the queue gets full?

Thanks.

RE: iOS mesh app discarding packets due to sequence number

Aleksander Nowakowski — Thu, 08 Oct 2020 19:57:15 GMT

Hello,

What version of the library are you using?

I don't know what's going on, how that numbers can get like that. It is either something with threading or how it get compiled. What else is wrong on the logs is that those messages are segmented and have the same seqZero, so reassemblyInProgress should be true and you should never get log message Discarding... for those messages.

My recommendations:

- upgrade lib to 3.0-beta1. This method has been improved in that version and perhaps works better when 2 messages are received very in short interval and processed in 2 threads.

- or initialize MeshNetworkManager with serial processing queue. By default the global one is used which is concurrent.

RE: iOS mesh app discarding packets due to sequence number

tesc — Thu, 08 Oct 2020 12:45:45 GMT

Hi,

To me it looks like the sequence number is correctly received by the network layer, but that something is wrong in the lower transport layer. I do not however see what, and have reached out to our mobile apps team. I expect to get some feedback within a week.

Regards,
Terje