Re: Clearing rows periodically - Mailing list pgsql-performance

From Tom Lane
Subject Re: Clearing rows periodically
Date
Msg-id 23422.1058535067@sss.pgh.pa.us
Whole thread Raw
In response to Clearing rows periodically  (Martin Foster <martin@ethereal-realms.org>)
List pgsql-performance
Martin Foster <martin@ethereal-realms.org> writes:
> My question is, should the purging of rows be done more often then once
> a day for both tables.   Is this why performance seems to take a hit
> specifically?

Given that the hourly purge seems to work well for you, I'd suggest
trying it on both tables.

Non-FULL vacuum is intended to be run *frequently*, say as often as
you've updated or deleted 10% to 50% of the rows in a table.  Delaying
it until you've had multiple complete turnovers of the table contents
will cost you.

> As there were too many rows purged for vacuum to
> accurately keep track of?

Only possible if you don't have the FSM parameters set high enough.
Infrequent vacuuming means you need more FSM space, btw.

            regards, tom lane

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