[mythtv-users] System Locking Up; seeing "TFW, Error: Write() -- IOBOUND"

[Andrew Casper]

On Nov 24, 2006, at 2:43 AM, Derek Battams wrote:

> Running a recent SVN build, and a day and a half ago my system just  
> started locking up.  The last thing I see in the logs is:
>
> 2006-11-22 20:07:43.558 TFW, Error: Write() -- IOBOUND begin cnt 
> (2048) free(1751)
>
> It seems to be happening only when recording two shows at once or  
> during a commflag or transcode job.  I checked the archives and I  
> saw some references to problems with fragmentation of the recording  
> partition, but seemed to be related to ReiserFS filesystems.  My  
> recording partition is XFS.  Regardless, I ran xfs_fsr on the  
> partition, but it's not helping at all.  Basically, my system locks  
> hard everytime I try to record two things simultaneously or run  
> commflag or transcode jobs.  However, today I recorded the football  
> game for 3.5 hours and it ran fine, but then while attempting to  
> record two shows at the same time tonight, it locked up.
>
> Any suggestions?
>
> Thanks,
>
> Derek

I use to see that when I was recording to a NFS mount. Increasing the  
read and write caches of the mount helped me, but I'm not sure you  
can do that with a XFS mount.

The unpopular answer is to try a larger HD Ring buffer (I think  
that's what it is called). It is an option in the setup menus. This  
is unpopular because you shouldn't need to do this (MythTV is specced  
to run on systems with 512 Mb) and many people complain because it  
adds another level of troubleshooting into the mix and. In my case, I  
have 2 gigabytes of RAM and it did seem to help.

- Andrew