|From:||Jeff Janes <jeff(dot)janes(at)gmail(dot)com>|
|To:||Harold A(dot) Giménez <harold(dot)gimenez(at)gmail(dot)com>|
|Cc:||Daniel Farina <daniel(at)heroku(dot)com>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Craig Ringer <ringerc(at)ringerc(dot)id(dot)au>, "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>|
|Subject:||Re: DELETE vs TRUNCATE explanation|
|Views:||Raw Message | Whole Thread | Download mbox|
On Thu, Jul 12, 2012 at 4:21 PM, Harold A. Giménez
> 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
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