Re: [HACKERS] LWLock optimization for multicore Power machines - Mailing list pgsql-hackers

From Bernd Helmle
Subject Re: [HACKERS] LWLock optimization for multicore Power machines
Date
Msg-id 1486414293.2018.2.camel@oopsware.de
Whole thread Raw
In response to Re: [HACKERS] LWLock optimization for multicore Power machines  (Alexander Korotkov <a.korotkov@postgrespro.ru>)
List pgsql-hackers
On Mon, 2017-02-06 at 22:44 +0300, Alexander Korotkov wrote:
> Results looks strange for me.  I wonder why there is difference
> between
> lwlock-power-1.patch and lwlock-power-3.patch?  From my intuition, it
> shouldn't be there because it's not much difference between them. 
> Thus, I
> have following questions.
> 
> 

Yeah, i've realized that as well.

>    1. Have you warm up database?  I.e. could you do "SELECT sum(x.x)
> FROM
>    (SELECT pg_prewarm(oid) AS x FROM pg_class WHERE relkind IN ('i',
> 'r')
>    ORDER BY oid) x;" before each run?
>    2. Also could you run each test longer: 3-5 mins, and run them
> with
>    variety of clients count?

The results i've posted were the last 3 run of 9 in summary. I hoped
that should be enough to prewarm the system. I'm going to repeat the
tests with the changes you've requested, though.




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