On Thu, Jul 12, 2012 at 4:21 PM, Harold A. Giménez
<harold.gimenez@gmail.com> wrote:
> Hi,
>
> I work with Daniel Farina and was the other engineer who "discovered" this,
> once again. That is, I got bit by it and have been running TRUNCATE on my
> test suites for years.
Hi Daniel and Harold,
I don't know if you followed this thread over into the -hacker mailing list.
There was some bookkeeping code that was N^2 in the number of
truncations performed during any given checkpoint cycle. That has
been fixed in 9.2Beta3.
I suspect that this was the root cause of the problem you encountered.
If you are in a position to retest using 9.2Beta3
(http://www.postgresql.org/about/news/1405/), I'd be interested to
know if it does make truncations comparable in speed to unqualified
deletes.
Thanks,
Jeff