[mythtv] different tags/branches side-by-side... was mythui

hendrixski at storsint.com hendrixski at storsint.com
Tue Feb 5 16:27:58 UTC 2008

>>>> How easy is it to put 0.20 and 0.21 side by side on one machine?
> How much disk space do you have?  If you can set aside 50 or 100 Gig for a
> separate partition, it's not hard.  Just create a good size empty
> partition,
> install linux and Myth trunk on it (just put everything in the one
> partition
> to keep it simple), give it a separate grub entry, and don't mount any of
> your production partitions from it.  Of course, you can't watch any of
> your
> already-recorded programs on your trunk install, or watch programs
> recorded
> while trunk was running on your production install.  But keeping the two
> worlds entirely separate is the safest thing.

I've run .21 trunk side-by-side with "heliocreek" (remember those guys
with the "friendly fork" based on .20 with mind-numbing code like "sudo
wget youtubevideo")  all on the same machine without partitioning, and
without virtual machines.  I was able to switch back and forth between the
two without having to log out or restart; just 2 or 3 commands in a
terminal, 10 seconds or less.

I used chroot.  It creates a filesystem within your filesystem in which
you can install Linux+mythtv, and it grows proportional to how much space
you use unlike a partition in which you have to set that space aside and
can't use.

Debian-based distro's have debootstrap and dchroot (which has a -d option
that allows you to share the xwindows session).  This way you can run
several branches of mythtv on the same machine in the amount of time it
takes to DL the bootstrap and compile Myth (as compared to paritioning,
installing, compiling).  Ubuntu has a lot of great documentation to get
you up and running in no time at all.

I'm sure RPM distro's must have similar tools.  Shouldn't be too hard to

You can mount certain folders to the chroot, like your home folder, or the
folder where you keep your recordings (they are compatible between
releases, right?) So that way you can reuse even more space, and swap
things between chroots.

oh... since you're sharing sockets.. make sure that mysqld isn't running
in the main session or in other chroots before you try it or you'll get
weird errors. Took me a while to figure that one out.  But it works well,
like I said I ran a .20 rip-off side by side with .21 trunk on the same
machine and all I needed to do to switch between the two was
* kill mythbackend
* stop mysqld
* exit chroot
* log-in to other chroot
* fire up mythtv

I was also able to delete the heliocreek thing once I tried it out by simply
unmounting the chroot and deleting it. 2 commands, like 10 secdonds. 
Compare that to repartitioning a drive.  :-p

I recommend it for testing and development. Enjoy!

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