[etherlab-dev] Possible Realtime Issues with Ethercat Master and RT Preempt Kernel

[Dr.-Ing. Matthias Schöpfer]

Hi!

We started using etherlab/ethercat and are quite impressed. Nice work!

We are running Linux with a RT_PREEMPT Kernel and e1000e ethercat
driver. We have to run at a cycle time of 1ms and we have jitter from
clock_nanosleep of about 15 microsecs max.

Nevertheless, we suffer from time to time from these:

EtherCAT WARNING 0: 2 datagrams UNMATCHED!
EtherCAT 0: Domain 0: Working counter changed to 9/9.
EtherCAT 0: Domain 0: Working counter changed to 0/9.

Especially, when we apply load to the system. From previous projects, I
experienced these effects when IRQ/Kernel Thread was not set to
appropriate RT Level.

My Question: has anybody experienced similar problems, and would it be
worth to investigate it. And if I decide to patch the kernel module,
where is a good starting point.

Thanks and regards,

	Matthias Schöpfer

-- 
Dr. Matthias Schöpfer
mz robolab GmbH
Marie-Curie-Str. 1
53359 Rheinbach

Office: +49 2226 83600 00
Fax: +49 2226 83600 11
Email: schoepfer at robolab.de

mz robolab GmbH
Vertretungsberechtigte Geschäftsführer: Dr. Rüdiger Maaß, Ralf Schulte
Registergericht Amtsgericht Bonn
Registernummer HRB 10595
---
This e-mail may contain confidential and/or privileged information. If
you are not the intended recipient (or have received this e-mail in
error) please notify the sender immediately and destroy this e-mail. Any
unauthorised copying, disclosure or distribution of the material in this
e-mail is strictly forbidden.

Diese E-Mail enthält vertrauliche und/oder rechtlich geschützte
Informationen. Wenn Sie nicht der richtige Adressat sind oder diese
E-Mail irrtümlich erhalten haben, informieren Sie bitte sofort den
Absender und vernichten Sie diese Mail. Das unerlaubte Kopieren sowie
die unbefugte Weitergabe dieser Mail ist nicht gestattet.
---
P    please consider the environment before printing this e-mail