9.10 recording fills disk; hangs

[cagney]

9.10 + 0.22 + (hopefully) latest from mythbuntu repo.

Connected recorders: PVR USB2; HVR-1950; HVR-950Q.

Scheduled recordings are starting but never stop. Eventually the disk fills (20kb left) and everything becomes stuck.

Grrr :-)

[cagney (andrew-cagney)]

I tried hand deleting a number of recordings from the AutoExpireList, freeing up sufficient disk space to record several programs without having to delete (auto-expire) anything. Worked, at least for the 3 small recordings I've so far tried.

This suggests the problem is in the code that is meant to keep space free by deleting recordings from the AutoExpireList.

[Mario Limonciello (superm1)]

So the best thing to do to start debugging this is running mythbackend with the "file" debug option.

Go modify /etc/default/mythtv-backend and change ARGS to

ARGS="--logfile /var/log/mythtv/mythbackend.log -v file"

You should get a lot more information in /var/log/mythtv/mythbackend.log after you restart mythbackend

$ sudo restart mythtv-backend

Share that log on this bug after it's ran for the default auto expirery period.

[cagney (andrew-cagney)]

Summary is that the AutoExpire code in 0.22 is less robust than 0.21 -0.21 checks that each expire succeeds and if it doesn't tries another file.

First here's a log from 0.21 where autoexpire ran during a recording (extra required set to 1gb):

2009-09-18 03:36:28.229 AutoExpire: CalcParams(): Max required Free Space: 2.0 GB w/freq: 15 min
2009-09-18 03:36:28.324 ProgramInfo, Error: GetPlaybackURL: '1061_20090903220000.mpg' should be local, but it can not be found.
2009-09-18 03:36:28.327 Expiring 4452 MBytes for 1038 @ Sun Sep 6 00:00:00 2009 => Babe

notice how it failed to delete the first file, but got a round this by deleting a second.

Now here's a similar log from 0.22 (extra required set to 5gb):

2009-11-27 14:59:13.207 AutoExpire: CalcParams(): Max required Free Space: 6.0 GB w/freq: 15 min
2009-11-27 14:59:13.307 ProgramInfo, Error: GetPlaybackURL: '1061_20090903220000.mpg' should be local, but it can not be found.

This time notice how it only attempted to delete a single file (and this failed); subsequent logs show it making further attempts to delete that same file. Eventually either the disk fills (what I was seeing), or autoexpire detects that to free up the required space it should delete multiple files.

Note that the "Error", in both cases, is caused by the database containing an expired program that doesn't have a corresponding MPG file (presumably it was lost during a crash; it refuses to be deleted).

So, to me, the underlying problem is that AutoExpire needs to be more robust (as it was in 0.21) and check that the file it deleted disappeared.

I can work around this by requiring a large amount of extra space.

[MarcRandolph (mrand)]

I did my best to explain it upstream. We'll see what happens. Thanks for the good explanation!

[Mario Limonciello (superm1)]

Upstream seems to believe that this should be fixed in r23054 or higher of trunk. You can test a newer revision of trunk by activating the autobuilds (at http://www.mythbuntu.org/auto-builds) and choosing 0.23. Please be sure to back up your database before doing this though, because you can't downgrade to 0.22 unless you drop the database and restore a backup.

Can you then provide feedback at that bug upstream (http://svn.mythtv.org/trac/ticket/7692)?

Thanks,

[MarcRandolph (mrand)]

Should have actually been fixed in the alpha4 disk for 10.04 (Lucid). If this is not the case, please open a new ticket with 0.23 results. Thank you!