Yes, but as the change did not alter the response time I used the original
view.
Anyway here are the response times using the changed view (without the
concatenation conditions):
with join_collapse_limit set to 8:
--
Marc,
You should expect that for the kind of OLAP workload you describe in steps 2
and 3 you will have exactly one CPU working for you in Postgres.
If you want to accelerate the speed of this processing by a factor of 100 or
more on this machine, you should try Greenplum DB which is Postgres 8.2
Scott Marlowe wrote:
>> random_page_cost = 1# units are one sequential page
>> fetch
>
> Seldom if ever is it a good idea to bonk the planner on the head with
> random_page_cost=1. setting it to 1.2 ot 1.4 is low enough, but 1.4
> to 2.0 is more realistic.
Which is probably t
Carlos H. Reimer wrote:
> Hi,
>
> I have changed the view to eliminate the bizarre concatenation conditions
> but even so the response time did not change.
Are you sure you did that? In the EXPLAIN it's still possible to see
them, for example
>-> Nested Loop (cost=1.34..3409.0
Hi,
I have changed the view to eliminate the bizarre concatenation conditions
but even so the response time did not change.
Changing the join_collapse_limit from 8 to 1 caused the decrease in response
time.
Here is the explain analyze with the join_collapse_limit set to 1:
Adriaan van Os wrote:
> Tom Lane wrote:
>
>> Somehow, autovac is doing something that makes the filesystem go nuts
>> every so often, and take an astonishingly long time to create an empty
>> file. But autovac itself doesn't create or delete any files, so what's
>> up here?
>> Also, I was able to
>>> On Mon, Jul 16, 2007 at 7:18 PM, in message <[EMAIL PROTECTED]>,
Tom Lane <[EMAIL PROTECTED]> wrote:
> Somehow, autovac is doing something that makes the filesystem go nuts
> every so often, and take an astonishingly long time to create an empty
> file. But autovac itself doesn't create or d
Tom Lane wrote:
Somehow, autovac is doing something that makes the filesystem go nuts
every so often, and take an astonishingly long time to create an empty
file. But autovac itself doesn't create or delete any files, so what's
up here?
Also, I was able to reproduce the variability in timing o
