Re: autovacuum not freeing up unused space on 8.3.0

Stuart Brooks wrote:
> It'll take a few minutes but I'll try and get the information to you. A
> summary is:
>
> Process 1:
> - writing 50 rows/second, 1 row/transaction.
> - every so often delete 100 rows
>
> Process 2:
> - running ANALYZE VERBOSE and pg_total_relation_size every second
>
> The result is that autovacuum appears to be canceled.


Why do have a second process that does an analyze every second?  That
seems like overkill and also if you let autovacuum do it, then it will
play better with vacuums when needed.  If you need autovacuum to
analyze more aggressively on this table you can change the table
specific thresholds.

I know that before 8.3 autovacuum wouldn't always keep up on tables like
this, but as of 8.3 with multiple simultaneous workers etc, it should be
much better.