what's the maximum BLE transfer speed beteen ESP32 and Nordic alike ble SOC

[kxJiang]

Is there any way to achieve maximum ble throughtput between ESP and NRF52832?
I tried to change the connection interval, but the parameter was denied by ESP32, because the BLE stack of ESP32 return 0x3b which means CONN_INTERVAL_UNACCEPTABLE. Are there any docs describing the minimum connection interval that ESP32 can accept?
Thanks!

[kxJiang]

Besides lower the connection interval, I have to extend the packet length for BLE. Luckily, ESP32's bluetooth stack accepts the MTU size exchange request issued by NRF52, resulting 247bytes/packet.Now the transfer speed between ESP32 and NRF52 using ble is up to about 12k bytes/s(with packet parsing and some request/response expense).Though it's far below the ideal 100kB/s trans speed claimed in this thread https://devzone.nordicsemi.com/question ... h-s132-v3/
I'm pleased with current result and I'll optimize this later on.