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Re: Unexpected page allocation behavior on insert-only tables

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Michael Renner <michael.renner@amd.co.at>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2010-05-31T03:44:02Z
Lists: pgsql-hackers 
On Sun, May 30, 2010 at 10:42 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> pretty clear what is going on.  See the logic in
> RelationGetBufferForTuple, and note that at no time do we have any FSM
> data for the bid table:

Is this because, in the absence of updates or deletes, we never vacuum it?

> 4. Now, all the backends again decide to try to insert into the last
> available block.  So everybody jams into the partly-filled block 10,
> until it gets filled.

Would it be (a) feasible and (b) useful to inject some entropy into this step?

-- 
Robert Haas
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