Re: Bloated pg_shdepend_depender_index

Gregory Maxwell wrote:

> I recently noticed that this database has grown to a huge size. ...
> Which I found to be somewhat odd because none of the tables have more
> than around 1000 rows. I hadn't been vacuuming because I didn't
> think that anything would ever be deleted.... so I performed a vacuum
> full... but no luck, it was still about 6.4GB.
>
> With some help of the folks on IRC I discovered...
> postgres=# select relname, pg_relation_size(oid) FROM pg_class ORDER
> BY 2 DESC LIMIT 2;
> relname | pg_relation_size
> -----------------------------+------------------
> pg_shdepend_depender_index | 159465472
> pg_shdepend_reference_index | 97271808
> (2 rows)

Huh, that's very strange.

The pg_shdepend table is a shared catalog, unlike most other catalogs.
Still I don't see why would the indexes not shrink. Do pg_authid,
pg_database, or pg_tablespace show a similar behavior? Is amarok
creating a lot of temp tables or something? When you did that vacuum
full, was there a process connected to the same or another database that
could be holding onto the pg_shdepend table?

I'll have a look at the code, but I thought I might throw that out, just
in case it rings a bell.

--
Alvaro Herrera http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support