Re: unsure - socketCAN blocking

[Steffen Rose <ro@emtas.de>]

Hello,

Am Montag, 8. Oktober 2012, 13:46:06 schrieb Marc Kleine-Budde:
> > I use:
> > Virtual box - Host Win 7/Guest kubuntu
> > Linux lisa 3.2.0-30-generic #48-Ubuntu SMP Fri Aug 24 16:52:48 UTC 2012
> > x86_64 x86_64 x86_64 GNU/Linux
> > 
> > SocketCAN connector is a EMS CPC-USB.

[...]

> Your program probably produces CAN frames faster than they could be
> delivered by your CAN hardware. Your choices are:

I'm unsure.
My CPU load is high. My application polling is not optimal at the moment. But 
the CAN busload is not so high.

At the moment I would think, it is more a problem internal or on USB. I'm 
unsure. I search information to analyze the current situation.

> 2) Increase txqueue length to 10000 or so.
>    (ifconfig can0 txqueuelen 10000)

I did it.

after a little bit time...

Now my error:
	write: Interrupted system call


$ ./candump can0

I see nothing.
But: There is traffic on the CAN and the USB traffic light of the CPC-USB is 
blinking. Means, the CAN-USB transfer data from the CAN to the socketcan CAN 
driver.

Can I see more states about the can, can_raw or the ems_usb modules?


$ ip -det -stat link show can0
4: can0: <NOARP,UP,LOWER_UP,ECHO> mtu 16 qdisc pfifo_fast state UNKNOWN qlen 
10000
    link/can 
    can state ERROR-ACTIVE restart-ms 0 
    bitrate 250000 sample-point 0.875 
    tq 250 prop-seg 6 phase-seg1 7 phase-seg2 2 sjw 1
    ems_usb: tseg1 1..16 tseg2 1..8 sjw 1..4 brp 1..64 brp-inc 1
    clock 8000000
    re-started bus-errors arbit-lost error-warn error-pass bus-off
    0          19         0          1          1          0         
    RX: bytes  packets  errors  dropped overrun mcast   
    18122      25463    19      0       0       0      
    TX: bytes  packets  errors  dropped carrier collsns 
    195038     164170   0       0       0       0      

-- 
Mit freundlichen Grüßen / Best regards

Steffen Rose