Re: Pg_upgrade speed for many tables

On Mon, Nov 5, 2012 at 4:42 PM, Bruce Momjian <bruce@momjian.us> wrote:
> On Mon, Nov  5, 2012 at 04:39:27PM -0500, Robert Haas wrote:
>> On Mon, Nov 5, 2012 at 4:33 PM, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
>> > AFAIR any transaction that modifies catalogs gets sync commit forcibly,
>> > regardless of the setting.  And sync commit means you get to wait for
>> > all previous transactions to be flushed as well.  So simply creating a
>> > temp table ought to do the trick ...
>>
>> I don't think there's a carve-out for system tables ... but creating a
>> temp table with synchronous_commit=on will certainly do the trick.
>
> What is a temp table writing to WAL?  The pg_class/pg_attribute changes?

Yes.

-- 
Robert Haas
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