Re: mysql to postgresql, performance questions - Mailing list pgsql-performance

From Scott Marlowe
Subject Re: mysql to postgresql, performance questions
Date
Msg-id dcc563d11003190651m73b4726emcde2552e9af732de@mail.gmail.com
Whole thread Raw
In response to Re: mysql to postgresql, performance questions  (Dimitri Fontaine <dfontaine@hi-media.com>)
List pgsql-performance
On Fri, Mar 19, 2010 at 3:04 AM, Dimitri Fontaine
<dfontaine@hi-media.com> wrote:
> Corin <wakathane@gmail.com> writes:
>> I'm running quite a large social community website (250k users, 16gb
>> database). We are currently preparing a complete relaunch and thinking about
>> switching from mysql 5.1.37 innodb to postgresql 8.4.2. The database server
>> is a dual dualcore operton 2216 with 12gb ram running on debian amd64.
>>
>> For a first impression I ran a simple query on our users table (snapshot
>
> For more serious impression and realistic figures, you could use tsung
> atop the http side of your application and compare how it performs given
> a certain load of concurrent users.
>
> In your situation I'd expect to win a lot going to PostgreSQL on
> concurrency scaling. Tsung is made to test that.

Exactly.  The OP's original benchmark is a single query run by a
single thread.  A realistic benchmark would use increasing numbers of
clients in parallel to see how each db scales under load.  A single
query by a single thread is pretty uninteresting and unrealistic

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