[mythtv-users] does myth 'best practice' have me adding anything to cron?

[steve]

> On Mar 23, 2016, at 1:10 AM, Stephen Worthington <stephen_agent at jsw.gen.nz> wrote:
> 
> On Tue, 22 Mar 2016 20:30:06 +0000, you wrote:
> 
>> On March 22, 2016 5:26:36 AM GMT, steve <stevenospam at gmail.com> wrote:
>>> Hi,
>>> 
>>> I'm running Ubuntu 14.04 LTS with MythTV 0.27.6 installed via PPA, not
>>> mythbuntu
>>> 
>>> Am I supposed to be manually adding anything to cron for myth?
>>> 
>>> For example, am I supposed to be crontabbing the running of
>>> mythfilldatabase every so often?
>>> 
>>> I found reference to some other cron files in some other thread, I am
>>> guessing mythbuntu-desktop or maybe myth-control-centre created them?:
>>> 
>>> /etc/cron.d/mythbuntu-bare
>>> /etc/cron.daily/mythexport
>>> /etc/cron.daily/mythtv-database
>>> /etc/cron.daily/optimize_mythdb
>>> /etc/cron.daily/optimize_mythdb.pl
>>> /etc/cron.weekly/mythtv-database 
>>> 
>>> Can someone post the contents of these so I can see what they do? 
>>> 
>>> Thank you
>> 
>> I too am running Ubuntu with mythtv packages installed on top, from the mythbuntu ppa, rather than installing from the mythbuntu ISO. I don't have mythbuntu-desktop installed, but do have mythbuntu-common, mythbuntu-bare-client and mythbuntu-control-center installed. I may have run mythbuntu-control-center in the past, but not for years.
>> 
>> Of the cron entries you list, I have just:
>> 	/etc/cron.daily/mythexport
>> 	/etc/cron.weekly/mythtv-database 
>> in my system. Using "dpkg -S" on the filenames, I see that /etc/cron.daily/mythexport comes from the mythexport package and /etc/cron.weekly/mythtv-database comes from the mythtv-database package. I suspect the people who have /etc/cron.daily/mythtv-database instead have manually moved the file from weekly to daily to make it occur more often.
>> 
>> If you don't have the cron entries but do have the mythexport and mythtv-database packages installed, I'm guessing the files were manually deleted. If so, there is probably a proper way to reinstall or reconfigure the packages to bring the cron files back, but I don't know how to do that.
>> 
>> John
> 
> mythbuntu-control-center is what installs the cron job for optimize.
> If you want to install it manually, you can find optimize_mythdb.pl
> here:
> 
> /usr/share/doc/mythtv-backend/contrib/maintenance
> 
> It is renamed to optimize_mythdb when installed in /etc/cron.daily by
> mythbuntu-control-center.  Running optimize_mythdb daily is highly
> recommended - doing so greatly reduces the likelihood of having
> database problems.  Most people who have posted over the last few
> years about having a problem with a database crash, when asked, had
> not been running optimize_mythdb regularly.  It actually repairs
> database errors even if they have not yet caused a problem.
> 
> Be aware that recent versions have this extra code at the bottom to
> defragment various tables:
> 
> # Defragement seek table
>    if ($dbh->do("ALTER TABLE `recordedseek` ORDER BY chanid,
> starttime, type")) {
>        print "Defragmented: recordedseek\n";
>    }
> # Defragement program table
>    if ($dbh->do("ALTER TABLE `program` ORDER BY starttime, chanid"))
> {
>        print "Defragmented: program\n";
>    }
> # Defragement video seek table
>    if ($dbh->do("ALTER TABLE `filemarkup` ORDER BY filename")) {
>        print "Defragmented: filemarkup\n";
>    }
> 
> With my massive database size (15235 recordings), I found that running
> those commands caused recordings happening at the same time to be
> corrupted (missing bits).  So I have commented out that code and now
> occasionally run it manually when I am sure I have enough time between
> recordings.
> 
> The /etc/cron.weekly/mythtv-database file is installed automatically
> as part of the mythtv-database package.  I copied it to
> /etc/cron.daily and altered it to do daily backups to another PC on my
> network.  That way, I get weekly backups on my MythTV box, and daily
> backups elsewhere.  I highly recommend daily backups as manually
> fixing more than a day's worth of recordings after a database crash is
> way too much.  If possible, it is best to have the database backups
> going to another hard disk than the one the database itself is on, as
> the backup process works the disk quite hard.  If the database is on
> SSD, both on the same drive should be fine.
> 
> Make sure that the disk the database is backing up to has enough room
> - the database backup works by exporting the entire mythconverg
> database as SQL code to a text file, and then going back and
> compressing that file with gzip.  So you need enough room for the
> temporary SQL copy of the database (huge) and the compressed copy
> (much smaller).  The default location for backups
> (/var/lib/mythtv/db_backups) defaults to being on the main system
> partition in normal Ubuntu/Mythbuntu installs.  That system drive is
> often not too large, and as your database grows, it can fill the drive
> and cause system crashes.  Putting the database backups on a recording
> drive may be a better idea, as mythbackend will ensure that there is
> always some free space on recording drives if it is allowed to do
> autoexpire.  That is what I did with my weekly backups, as I always
> ensure I have plenty of free space for new recordings and add new hard
> drives as necessary to keep enough free space available.
> 
> The /etc/cron.daily/mythexport file is installed automatically as part
> of the mythexport package, if you are using that.
> 
> I do not have a /etc/cron.d/mythbuntu-bare file, and I have no idea
> what it would be for.
> 

Thank you.  This is great info and I've added to my all too extensive mythtv notes file,  thanks again.