Hi André,
I have an idea ;-)
On 12/03/2020 18.43, André Hartmann wrote:
can someone help me interpreting the following ip output:
ip -s link show can1
3: can1: <NOARP,UP,LOWER_UP,ECHO> mtu 16 qdisc pfifo_fast state
UNKNOWN mode DEFAULT group default qlen 100
link/can
RX: bytes packets errors dropped overrun mcast
0 9987413 1 74 1 0
TX: bytes packets errors dropped carrier collsns
0 0 0 0 0 0
I'm especially interested in the meaning of the
* 1 errors
* 74 dropped
* 1 overrun
E.g. if you look into
linux/drivers/net/can/sja1000/sja1000.c
you can see that an overrun error also triggers the error counter to
increase - that's why both are set to 1.
The reason for the overrun error is a notification from the CAN
controller itself. It tells us that the received CAN frame has not been
read from the controller until the next CAN frame arrived.
The dropped counter usually indicates that the CAN driver did not get a
skbuff data structure (e.g. out of memory condition).
This is NOT good. What CAN hardware/setup are you using?
Regards,
Oliver
