Hi Chris, On Wed, Mar 27, 2024 at 5:04 PM Chris Laplante <Chris.Laplante@xxxxxxxxxx> wrote: > > Thanks Luiz > > They are not trying to maintain 30 simultaneous connections if that is what you question was. They will only connect with say one at a time but they want to maintain up to 30 bonded devices in their database. I have something like that in my device database, in fact in a crowded environment you may see hundreds, perhaps they are marked with auto-connect flag and then at some point you can't really pair more because they are always connecting/disconnecting? > Thanks > Chris > > -----Original Message----- > From: Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx> > Sent: Wednesday, March 27, 2024 5:01 PM > To: Chris Laplante <Chris.Laplante@xxxxxxxxxx> > Cc: linux-bluetooth@xxxxxxxxxxxxxxx > Subject: Re: Maximum Bonded Devices > > EXTERNAL EMAIL: Be careful with attachments and links. > > Hi Chris, > > On Wed, Mar 27, 2024 at 2:15 PM Chris Laplante <Chris.Laplante@xxxxxxxxxx> wrote: > > > > Hi, > > > > I have a customer with an issue where they are unable to get 30 devices paired and bonded when the BL5340PA (nRF5340) SoC as their central device. > > > > Following details might help you out- > > 1. They are using the hci_usb sample code as the firmware on the SoC. > > 2. The stack on the host Linux system being used is BlueZ (version 5.66) > > > > They are able to pair and bond with upto 8 devices pretty quickly and then this process slows down and they aren't able to pair with more than 12-15 sensors in a single go. > > After the pairing and bonding process stagnates at around 12-15 sensors if they restart the host system (and in turn the SoC as well) they are able to pair with a few more sensors but not 30 sensors. > > So far out of the things that they have tried out to identify the source of the problem it has something to do with the BlueZ stack configuration ( they are currently using the default stack configuration) and/ or the firmware configuration parameters. > > > > Do you have any idea on what configuration parameters could be causing this behaviour and/ or what configuration changes need to be made so that they can achieve the target of pairing and bonding with 30 sensors. If you have any more questions please let me know. > > Don't think there is such thing about number of paired devices limit, we just use lists so they be extended dynamically as you pair with more devices, there might be a limit on how many the controller can maintain connected simultaneously though, so perhaps you want to explain a little better how the process of pairing goes, is that serialized or you attempt to connect/pair everything in parallel? > > > I believe the default is set to something like 65K devices per > > MaxControllers in main.c as well as main.conf > > > > parse_config_u16(config, "General", "MaxControllers", > > &btd_opts.max_adapters, > > 0, UINT16_MAX); > > > > # Maximum number of controllers allowed to be exposed to the system. > > # Default=0 (unlimited) > > #MaxControllers=0 > > These are the number of controllers, not to confuse with paired devices though. > > > I am assuming the issue isn't BlueZ specific but if there is any thoughts or guidance you may have it would be appreciated. > > > > Thanks > > Chris > > > > THE INFORMATION CONTAINED IN THIS DOCUMENT IS OF A PROPRIETARY NATURE > > AND IS INTENDED TO BE KEPT CONFIDENTIAL BETWEEN THE SENDER AND THE > > INTENDED RECIPIENT. IT MAY NOT BE REPRODUCED OR USED WITHOUT EXPRESS > > WRITTEN PERMISSION OF EZURIO > > > > -- > Luiz Augusto von Dentz > THE INFORMATION CONTAINED IN THIS DOCUMENT IS OF A PROPRIETARY NATURE AND IS INTENDED TO BE KEPT CONFIDENTIAL BETWEEN THE SENDER AND THE INTENDED RECIPIENT. IT MAY NOT BE REPRODUCED OR USED WITHOUT EXPRESS WRITTEN PERMISSION OF EZURIO -- Luiz Augusto von Dentz