Re: autovacuum for large periodic deletes - Mailing list pgsql-admin

From Chris Browne
Subject Re: autovacuum for large periodic deletes
Date
Msg-id 60y7x07273.fsf@dba2.int.libertyrms.com
Whole thread Raw
In response to Re: autovacuum for large periodic deletes  ("Sriram Dandapani" <sdandapani@counterpane.com>)
List pgsql-admin
sdandapani@counterpane.com ("Sriram Dandapani") writes:
> About 5-10 million rows stay after deletion. There are a few other
> tables where the daily deletion totals about 3-6 million.

It would appear there is something fairly not-sane about the process,
then.  You delete about 90% of the day's data from the table each day?
That's a *lot*, and you are quite likely to have trouble with this
table blowing out the Free Space Map as a result.

> Would a vacuum full/cluster affect other operations. These tables
> have a 24x7 high data insertion rate.

Yes, VACUUM FULL and CLUSTER would block other operations while they
run.

The real Right Answer probably involves having data flow into some
sort of "queue" table, created fresh each day, for that day's
activities, where, at the end of the day, all of the data either gets
purged or moved to the "final destination" table, so that a new table
can be created, the next day.
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