Other Parts Discussed in Thread: CC3135
Hello,
I see long random delays in sending IP packets over a raw socket using sl_Send() command when I send UDP or TCP packets every 2..10ms. This delay often appears within 3…15 minutes and can last up to 3.6 seconds (!?). There is no clear pattern when the delay starts and how long it lasts. I also see much shorted delays lasting for 10…250ms. They appear more often, especially when the packet rate increases.
The socket was open using sl_Socket(SL_AF_PACKET, SL_SOCK_RAW, 0) command and the NWP was placed in the Network Bypass Mode (p.108, SWRU455M – FEBRUARY 2017 – REVISED OCTOBER 2020).
The power policy is SL_WLAN_NORMAL_POLICY. It can also be SL_WLAN_ALWAYS_ON_POLICY with the same result. The signal strength is from good to excellent: -55dBm…-33dBm. The transmitting channel is in the 2.4GHz frequency band. WLAN mode does not matter.
The socket can be in blocking or unblocking mode. The FlowContCB.TxPoolCnt value drops to FLOW_CONT_MIN and no more packets can be sent during the delay. After the delay, everything gets back to normal. There are no reported WLAN disconnection/connection events during the delay.
Is there a way you can fix this issue on the NWP side – long delays are not acceptable? Alternatively, please let me know if I hit an undocumented NWP constrain and if there is a way to mitigate it.
Thanks,
Olek Bogush