[mythtv-users] Performance issue : Number of records in a Table ???

[Michael T. Dean]

On 03/07/2006 09:57 AM, Dhiraj K wrote:
> just want to clear my doubts...
> what happens if the size of a table ( say "program" table, or any 
> other), keeps on increasing...as we update our boxes everytime.
>
> so after a few months( or a year) of updates, the tables might have 
> thousands of records...
>
> does this slow down the mythtv-box's performance ???
> does it take longer for mythfilldatabase to update ?
> does this have a problem during an INSERT into the table ?
> does mythtv automatically clear out "not needed" records ( i.e. 
> records that a couple of months old) from time to time ?
> is there any setting for this ?

I'm ignoring all the questions except the last two (which make the 
others irrelevant).  The mythfilldatabase program will automatically 
clear expired program listings from the database.  By default, they 
expire one day after the starttime.  However, if you pass the 
mythfilldatabase command-line argument "--no-delete", they expire one 
week after the starttime.

Therefore, you'll never have more than 3 weeks worth of program listings 
in your database.

To make sure you get good performance from your database, check out 
Chris Petersen's script optimize_mythdb.pl in the contrib directory.  
The comments at the top of the script explain how to use it properly 
(from a cron job).

Mike