[mythtv-users] Wiki: Balanced Disk I/O

[Stephen Worthington]

On Tue, 11 Aug 2015 13:44:50 -0400, you wrote:

[snip]
>FWIW, Combination used to be the default (and, there was good reason for 
>it--as it's most appropriate for all systems). Then users complained 
>that after they put in their new 2TB drive when their old 2TB drive 
>filled up, MythTV was still recording to the old drive and expiring 
>shows when they had plenty of space on the new drive.  So, the default 
>was changed to Balanced Free Space so that users who put in empty drives 
>wouldn't be surprised.  However, this setting (er, actually, the 
>algorithm) is broken for anyone who doesn't have at least one drive with 
>a significant portion of free space (therefore, it's a broken design, 
>made available at popular request, but it is not a bug).  The proper 
>solution for users with full drives who add new drives is to manually 
>move some portion of recordings from full file systems to less-full file 
>systems to balance recordings--ideally some "representative" sample of 
>recordings, meaning about equivalent in age and/or priority and/or 
>"LiveTVness"/"Watchedness"/"Deletedness".  That said, you can make the 
>argument that setting the default Storage Group Disk Scheduler to 
>Balanced Free Space /is/ a bug (and I won't argue that it's not).
[snip]

If anyone wants to balance the free space on their drives after adding
a new drive, they could try the script I wrote for this.  It selects
recordings at random from the fullest drive to move to the least full
drive until the free space is roughly balanced.  It is available on my
web server:

  http://www.jsw.gen.nz/mythtv/balance_storage.sh