[mythtvnz] Mythbuntu 16.04 user experiences

[Stephen Worthington]

On Tue, 19 Jul 2016 08:15:00 +1200, you wrote:

>On Tue, 19 Jul 2016 04:31:49 +1200, Stephen Worthington  
><stephen_agent at jsw.gen.nz> wrote:
>
>
>>
>> If you have not already upgraded to MythTV 0.28, it would be sensible
>> to do that first on your current system, if possible.  Then do the OS
>> upgrade separately.
>>
>> One problem I have found with my testing of 16.04 so far is that the
>> new version of mysql is using the editline library (from FreeBSD?)
>> instead of the readline library in its utility programs.  Since I use
>> the SQL command line quite a bit, that is a serious problem for me as
>> editline does not do the right sort of things for bringing back
>> commands out of my command history for me to re-use.  So on my test
>> box, I replaced mysql with MariaDB, which still uses readline and is
>> going to keep doing so.
>>
>> Apparently Oracle have a problem with the GPL (or is it LGPL) license
>> and are trying to remove all such software from mysql, so they will
>> not be going back to readline, despite the bug reports filed about
>> this problem.  So it is unlikely I will ever be using mysql again as
>> this problem is a deal breaker for me.
>>
>> Fortunately, MariaDB seems to work just fine as a replacement for
>> mysql.  It is now the default database in Fedora anyway, and no one
>> seems to be complaining about problems.  Swapping to it was far from
>> easy though, as the process results in uninstalling of the MythTV
>> packages before the change can happen.  And the mythexport package
>> seems to be built with the wrong dependency, as it requires the real
>> mysql packages and wants to uninstall MariaDB and reinstall mysql if
>> you try to install it.  I need to file a bug report with the Mythbuntu
>> maintainers about that.
>>
>> So if you want to switch to MariaDB also, make sure you have a good
>> backup of your MythTV database.
>>
>> I am still debating with myself about whether I will be upgrading in
>> place from 14.04 to 16.04.1 when it comes out, or whether I will move
>> my database over to a new 16.04.1 install.  I have done both types of
>> upgrade in the past, and there are problems and benefits for both
>> paths.  At least I now have an ultra-fast SSD drive to boot from, so
>> the upgrade process will be able to be done in the available time
>> between recordings - my MythTV box is pretty busy most days, but there
>> is usually one or two days a week with a gap of 8 hours or so between
>> recordings.  Without the SSD, I am not sure if 8 hours would be enough
>> to safely do a full upgrade.
>>
>
>Thanks for the detailed reply.I don't use the SQL command line due to fear  
>and ignorance.You don't mention any other problems so I take it that it  
>has no other major problems?
>I'm still on 12.04 and,correct me if I'm wrong,there is no upgrade path  
> from that.I intend to install the new system on an SSD but keep 12.04 on  
>it's original drive until I'm happy that everything is running.

I have not found anything else that is a problem, so far.  I am sure
you can upgrade from 12.04 LTS to 16.04 LTS if you do it in two steps
by upgrading to 14.04 first.  With an SSD that might not take too long
to do so it could be worth trying.  Running 12.04 from an SSD is
probably not a good thing to try as it does not have full support for
SSDs.  If the SSD is a SATA one, it will likely work, but I think
there will not be any fstrim support.  If the SSD is NVME (PCIe), it
likely will not have the right drivers.  Even with 16.04, the version
of smartmontools is not new enough to support my SSD Samsung 650 Pro
NVME SSD, so I had to manually install a newer version.

With the MythTV upgrading, make sure you read all the release notes
for all the new versions between your current version and 0.28.  There
are some manual things you need to do on some upgrades, such as
install the extra timezone support needed for when MythTV converts to
using UTC instead of local time.

Using the SQL command line need not involve fear, as you can easily
use it completely safely for queries without ever doing anything that
changes the database.  If you only use the show, desc and select
commands, there is no danger.  My most frequent use of SQL commands is
to do searches of the recorded, oldrecorded and program tables to see
if I have previously recorded or watched something.  I find that the
EPG here in NZ is so bad at times that MythTV will be re-recording an
entire series of something that has different EPG but I already have a
copy of.  An example is New Tricks, where the current series on UKTV
is the same as one I already have, and the descriptions mostly match,
but there are enough differences that mythbackend is re-recording them
all.