SMP Server DFU very slow

[fgeldenh]

I have been using the DFU on nRF5 SDK for some years now and we use this feature to update firmware in the field.

I have sucessfully managed to get the SMP Server sample working on my custom board. However the different is performance is significant. nRF Connect sample is slow.

Are there any suggestions as to how to improve the performance.

Is there not an equivalent DFU feature in nRF Connnect to the nRF5 SDK? 

I have read about the nRF Secure Immutable Bootloader (B0), but have not found sample that works.. Would this option be faster?

If so, could you point me to a working sample.

Thank You

[Kenneth]

fgeldenh said:

Are there any suggestions as to how to improve the performance.

Are you able to create an on air BLE sniffer log so we can theorize a bit what may improve throughput?
https://www.nordicsemi.com/Products/Development-tools/nRF-Sniffer-for-Bluetooth-LE (you need a spare nRF52/nRF52840-DK)
https://infocenter.nordicsemi.com/topic/ug_sniffer_ble/UG/sniffer_ble/intro.html (I suggest download the user guide in pdf)

Kenneth

[fgeldenh]

Hi - I have taken traces from IOS and Android nrfConnect for Mobile.

androidcapture.pcapngioscapture.pcapng

[Kenneth]

Looking at the traces I can see that much of the data is fragmented, this is because the peripheral have not enabled data length exentsion (DLE). Can you follow the project settings from the throughput example on how to enable DLE:
https://github.com/tejlmand/fw-nrfconnect-nrf/blob/master/samples/bluetooth/throughput/prj.conf

In addition I can see that the connection interval is about 48.75ms, if possible you should try to reduce the connection interval (e.g. 30ms) should speed thing up.

The implementation is different from the nRF5 SDK, so you can't get the same performance in terms of throughput, but hopefully the above should help some.

Hope that helps,
Kenneth