autovacuum on updated rows

I am using new postgres 8.1 and also trying out the integrated autovacuum. I have a concern.

I have a table where I perform an update on a row every 10 seconds. The table is VERY small. Hardly any INSERTS, no DELETES, and a ton of UPDATES.

adbs_db=# select count(*) from volumes;
count
-------
7
(1 row)

I am looking at the file sizes that correspond to this table and its indeces. They are growing -- I think I understand why -- dead rows are occuring on an UPDATE. But what I don't understand is why autovacuum has not kicked in-- I have kept the default values on autovacuum.

In about 50 minutes' time, the table itself has grown 2MB, and each index has grown by about 1MB

Will autovacuum eventually run on this table???? What rows/columns does autovacuum look at to determine when to work on a table? I'd like to look at those rows, too.

Thanks!!
Steve


adbs_db=# \d volumes
Table "public.volumes"
Column | Type | Modifiers
------------------+------------------------+--------------------
label | character varying(128) | not null
imported | boolean | not null
closed | boolean | not null
active | boolean | not null
online | boolean | not null
offline | boolean | not null
archiver_name | character varying(32) | not null
environment_name | character varying(32) | not null
curr_size | bigint | not null default 0
vol_num | integer | not null
start_time | integer |
stop_time | integer |
Indexes:
"volumes_i1" unique, btree (label)
"volumes_i2" btree (environment_name)

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