Re: Index size increases after VACUUM FULL

On Tue, Sep 30, 2008 at 4:49 PM, Heikki Linnakangas <
heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:

> Gurjeet Singh wrote:
>
>> On Tue, Sep 30, 2008 at 3:09 PM, Heikki Linnakangas <
>> heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
>>
>>> That's normal. VACUUM FULL creates new index pointers for the tuples it
>>> moves, which can lead to a bigger index. If it bothers, REINDEX will pack
>>> the indexes tighter again.
>>>
>>
>>
>> That explains it... and yes, REINDEX did bring the index size back to
>> normal.
>>
>> Would it make sense to mention this in docs of VACUUM FULL? Either at
>>
>> http://www.postgresql.org/docs/8.3/static/routine-vacuuming.html
>>
>> or at
>>
>> http://www.postgresql.org/docs/8.3/static/sql-vacuum.html
>>
>
> Yeah, maybe. Want to suggest a wording?

VACUUM FULL may cause a noticeable increase in size of the indexes of the
tables that are vacuumed; this is because the VACUUM operation makes new
entries in the index for the tuples/rows that have just been moved.

OR

VACUUM FULL may cause a noticeable increase in size of the indexes, that are
on the tables being vacuumed; this is because the VACUUM operation makes
new entries in the index for the tuples/rows that have just been moved.

Followed By:

An appropriate REINDEX command (REINDEX database|table|index ) can reduce
the size of such indexes.

I think it makes sense to put this on both the above mentioned URLs.

Best regards,
--
gurjeet[(dot)singh](at)EnterpriseDB(dot)com
singh(dot)gurjeet(at){ gmail | hotmail | indiatimes | yahoo }.com

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