Re: pg_dump is O(N) in DB table count N even if dumping only one table

Hi,

On 2013-06-10 14:24:14 +0000, Gunnlaugur Thor Briem wrote:
> So I ran this again locally on the production server:
>
> duration: 16012.518 ms statement: SELECT c.tableoid, c.oid, c.relname, ...
> duration: 16516.708 ms statement: SELECT tableoid, oid, typname, ...
> duration: 13400.694 ms statement: SELECT classid, objid, refclassid, ...
>
> Duration decrease is probably *not* significantly due to a warmer cache,
> because I had two runs over the slow network and their durations were
> similar (actually longer the second time).

Hm. 13s for pg_depend locally vs 55s remotely. You need to have a
tremendous amount of dependencies.
Could you do a count(*) of pg_depend, pg_type and pg_class?

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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