[mythtv-users] Backend seems to be crashing frontend

[Michael T. Dean]

On 08/16/2008 10:29 AM, Kevin Kuphal wrote:
> On Sat, Aug 16, 2008 at 4:38 AM, Allen Edwards wrote:
>> I don't know what to title this.  Yesterday, my frontend started
>> locking up when I tried to watch a show.  I restart the frontend and
>> can watch most of the shows.  But if I ESC the show, sometimes when I
>> go back to the same show, it locks up. Sometimes they don't lock up,
>> just show a black screen.  Once one show won't play, nothing will and
>> I either have to restart X or the reboot the computer.
>>
>> I have a combined system mythbuntu 8.04 and a frontend only 8.04.1.
>> Both frontends experience the same problem, which to me points to the
>> backend.  I have had to restart the backend a couple time to get the
>> system going again.
>>
>> I see lots of errors that just started in the backend log about the
>> same time this problem started. Older logs show no errors.  The only
>> thing I have done is get this frontend only system running but have
>> not touched the combined system at all.
>>
>> The most interesting errors from mythbackend.log look like this:
>>
>> 2008-08-15 14:18:23.501 DB Error (Error in JobQueue::GetJobCmd()):
>> Query was:
>> SELECT cmds FROM jobqueue WHERE id = 340;
>> Driver error was [2/2006]:
>> QMYSQL3: Unable to execute query
>> Database error was:
>> MySQL server has gone away
>>     
> Looks like your database is crashing.  Seems to be a MySQL problem.  I would
> suggest updating your mysql-server packages unless you recently updated them
> prior to this issue then moving back to the previous version might be an
> option.  Check you /var/log/mysqld logs to see what might be going on.  If
> the database disappears, Myth will exhibit all sorts of problems.
>   

Or, if you're using trunk, it's a known issue with the non-stable 
development code...  (There have been some commits that may help or even 
fix the issue--but anyone running trunk would know that because they'd 
be reading the commits list--so you may want to update.)

> The script you're looking for is myth_optimize_db.pl I think.

close--it's optimize_mythdb.pl :)  (And it's from the contrib directory 
of the Myth source distribution.)

>   You can also
> just use the standard mysqlcheck program (which is what the script does)

Actually uses a different approach, but accomplishes the same, and more.

Mike