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Tsirkin" , Jason Wang , Xuan Zhuo , linux-can@vger.kernel.org, virtualization@lists.linux.dev, Wolfgang Grandegger , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Stefano Garzarella References: Content-Language: en-US From: Oliver Hartkopp In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 06.01.26 17:50, Harald Mommer wrote: >> With the plain 'cangen' you are not really flooding the interface, since >> you are only sending a random CAN frame every 200ms. The only way I can >> reproduce this behaviour in a consistent manner is running from the host: >> >> while true; do cansend vcan0 134#00; done >> >> which seems to generate the maximum amount of traffic. >> >> This is not of course a realistic bus load, but is leading the system >> (at least on my setup) to a corner case somewhere. > > I have no idea how long the shell needs for a loop, always used cangen -g 0 to stress the setup which is most probably faster than the shell interpreter, and sometimes did this for both directions (RX and TX). > > Full load is a realistic setup. And even if it was not, if something stopped working or worse crashes torturing the setup this was a problem. > Yes. cangen -g 0 -i creates full load - even on real CAN interfaces. You can also generate fixed content if you want to omit the generation of randomized content. 'cangen -?' prints a help text. Best regards, Oliver