[mythtv-users] mythtv hard lockup

[R. G. Newbury]

David Rees wrote:
> On 12/20/06, R. G. Newbury <newbury at mandamus.org> wrote:
>> Ohh you are whining about *nothing*!  When MY frontend crashes, MY
>> lockup is worse than yours!!
> 
> LOL, I don't think we're whining, but it's obvious that you are. :-P


I'm not whining. I'm BOASTING!

> 
>> I am using a Via motherboard... which suggests that:
>>
>> a)      there are a number of different lockup triggers..as the nvidia driver
>> cannot be causing my lockup...unless it is within the common portions of
>> the openchrome driver (I understand the nvidia driver has common code)
>> or its in X (drm, dri etc.)
>> or
>> b)      it is something withing Mythtv, probably a race condition, which
>> might be related to lirc or affected by lirc. I discount ivtv as all of
>> my lockups occur during playback.
> 
> In your case, I would strongly suspect the Openchrome drivers or some
> other memory/DMA bandwidth issue since you note that it tends to
> happen during fast forward or rewind when the video is likely being
> pushed hard and a some disk activity is taking place... How to narrow
> it down... I'm not sure. Are there any good Linux stress test tools?


Well there is something weird going on. I had a lockup 2 nights ago, and 
  I was able to slowly back out and get to a console. The mouse cursor 
was on top of the mythfrontend window close button. I clicked that, and 
the main portion of the screen 'sorta' disappeared. Eventually an error 
message box came up...'Window titled mythfrontend has ceased to 
respond...' etc. But I could not terminate it. I got into a console 
(which responded reasonably quickly) and tried to kill the given PID, 
but that was ineffective. It took 27 minutes from my clicking the close 
button, to get to a console....(The backend was recording a show, so I 
did not want to kill the box). The various windows ended up writing on 
top of each other. I could see mythfrontend messages in the console 
window where it was started, but the mythfrontend display window top 
frame was still on-screen and some desktop icons were showing through 
too...like the mythfrontend window had been minimized...,

Although lockups are not normally userland events, this really made me 
wonder that it might be a myth <-> X interaction.

So how would we trace something like this? I'd like to help but I have 
no idea where to start.

Geoff