Re: index file bloating still in 7.4 ? - Mailing list pgsql-performance

From Tom Lane
Subject Re: index file bloating still in 7.4 ?
Date
Msg-id 4250.1066754575@sss.pgh.pa.us
Whole thread Raw
In response to Re: index file bloating still in 7.4 ?  (Seum-Lim Gan <slgan@lucent.com>)
List pgsql-performance
Seum-Lim Gan <slgan@lucent.com> writes:
> We did a few (like 5 to 8 times) vacuum analyze <tablename> (no full), the
> pg_statistics relfilenode grew.

Well, sure.  ANALYZE puts new rows into pg_statistic, and obsoletes old
ones.  You need to vacuum pg_statistic every so often (not to mention
the other system catalogs).

> If we do plain simple "vacuum <tablename>" (again no full), we see
> pg_statistics_relid_att_index relfilenode grew instead of
> pg_statistics.

Don't think I believe that.  Plain vacuum won't touch pg_statistic
at all (unless it's the target table of course).  I'd expect ANALYZE
to make both the stats table and its index grow, though.

            regards, tom lane

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