Re: Suspeneded task causes EPICS crash

[Burkhard Kolb <b.kolb@gsi.de>]

Hi Erik,

I had the same behaviour when a can bus device produced many 
CAN-messages
due to an error condition. This caused the ring buffer of the canbus 
receive task to overflow.
I temporarily increased the buffer to 3000 entries which helped. The 
real cure of course
was to fix the problem on the device.

Burkhard

On 06.12.2005, at 02:00, Erik Johansson wrote:

> Hi all,
>
> We are getting the following message on one of our IOCs. The CA event
> task gets suspended, which effectively kills EPICS, as all channels
> become disconnected after that:
>
> task 1aa53f8 CA event suspended
> ./taskwd.c" line number=175
> callbackRequest ring buffer full
>
> From digging in the source code, it looks like enough callback requests
> are requested to cause the ring buffer to overflow. We use the default
> size of 2000 entries for the buffer.
>
> Has anyone seen a failure like this before? Any advice on what to 
> pursue
> as far as troubleshooting?
>
> I am concerned that simply increasing the number of entries in the
> buffer may just be putting a band-aid on a bigger problem.
>
> Thanks,
>
> Erik
>
> ****************************************
> Erik M. Johansson
> Adaptive Optics Software Engineer
> W. M. Keck Observatory
> 65-1120 Mamalahoa Hwy
> Kamuela, HI 96743
> Tel: 808-885-7887
> Fax: 808-885-4464