Re: PostgreSQL and sql-bench

Hi.

Do you compare apples to apples? InnoDB tables to PostgreSQL? Are all
needed indexes available? Are you sure about that? What about fsync?
Does the benchmark insert a lot of rows? Have you tested placing the
WAL on a separate disk? Is PostgreSQL logging more stuff?

Another thing: have you analyzed the tables? Have you tested higher
shared_buffers?

And the last thing: there are lies, damn lies and benchmarks. What
does a benchmark, which might be optimized for one DB, help you with
your own db workload?

There are soooo many things that can go wrong with a benchmark if you
don't have real knowledge on how to optimize both DBMS that it is just
worthless to use it anyway if you don't have the knowledge ...

PostgreSQL outperforms MySQL in our environment in EVERY situation
needed by the application. So, does the benchmark represent your work
load? Does the benchmark result say anything for your own situation?
Or is this all for the sake of running a benchmark?

cug

On 9/21/06, yoav x <yoav112003(at)yahoo(dot)com> wrote:
> Hi
>
> After upgrading DBI and DBD::Pg, this benchmark still picks MySQL as the winner (at least on Linux
> RH3 on a Dell 1875 server with 2 hyperthreaded 3.6GHz CPUs and 4GB RAM).
> I've applied the following parameters to postgres.conf:
>
> max_connections = 500
> shared_buffers = 3000
> work_mem = 100000
> effective_cache_size = 3000000000
>
> Most queries still perform slower than with MySQL.
> Is there anything else that can be tweaked or is this a limitation of PG or the benchmark?
>
> Thanks.

--
PostgreSQL Bootcamp, Big Nerd Ranch Europe, Nov 2006
http://www.bignerdranch.com/news/2006-08-21.shtml