interesting post at https://github.com/peterhinch/micropython-mqtt/issues/95 dated 06 October 2022:
After spending some (a lot) more time investigating this, we finally found some answers. We did some tests with Wireshark packets of predefined length, so we could recognize them in the traffic with Wireshark. Whenever there are multiple MQTT messages in the same TLS packet/frame, the MQTT would arrive out of order on the broker side. This seems to be an error in the processing of our broker. It seems that the esp32 (and maybe TLS, I am not familiar with it) prefers packets sizes of around 1500 bytes, and this seems to cause some issues with our broker. I am uncertain if this impacts any other users, as I do not know what AWS IoT core uses under the hood. so, maybe the sequencing issue is actually caused by how paho mqtt library demuxes single tcp packet into multiple mqtt messages when queuing..? (if multiple messages from same device but with diff timestamps can end up in same tcp packet) ⊣GE⊢ > On 18 May 2026, at 11:12 am, Graham Eddy <[email protected]> wrote: > > needs to be clever applying new timestamps to allow for multiple out of > sequence packets > ⊣GE⊢ > >> On 17 May 2026, at 10:52 pm, [email protected] <[email protected]> wrote: >> >> I’m looking at adding an option that would allow MQTTSubscribeService to >> update packets with timestamps less than the previous one. This would give >> the processing choice to the user of MQTTSubscribeService > > > -- > You received this message because you are subscribed to the Google Groups > "weewx-user" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To view this discussion visit > https://groups.google.com/d/msgid/weewx-user/A56895AD-323A-4003-8862-DCC48251C683%40geddy.au > > <https://groups.google.com/d/msgid/weewx-user/A56895AD-323A-4003-8862-DCC48251C683%40geddy.au?utm_medium=email&utm_source=footer>. -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/weewx-user/201200AD-E12F-41F2-A27C-76D42A621480%40geddy.au.
