Re: gaussian distribution pgbench

On Mon, Mar 17, 2014 at 7:07 PM, KONDO Mitsumasa
<kondo.mitsumasa@lab.ntt.co.jp> wrote:
> (2014/03/17 18:02), Heikki Linnakangas wrote:
>>
>> On 03/17/2014 10:40 AM, KONDO Mitsumasa wrote:
>>>
>>> By the way, you seem to want to remove --gaussian=NUM and
>>> --exponential=NUM
>>> command options. Can you tell me the objective reason? I think pgbench is
>>> the
>>> benchmark test on PostgreSQL and default benchmark is TPC-B-like
>>> benchmark.
>>> It is written in documents, and default benchmark wasn't changed by my
>>> patch.
>>> So we need not remove command options, and they are one of the variety of
>>> benchmark options. Maybe you have something misunderstanding about my
>>> patch...
>>
>>
>> There is an infinite number of variants of the TPC-B test that we could
>> include
>> in pgbench. If we start adding every one of them, we're quickly going to
>> have
>> hundreds of options to choose the workload. I'd like to keep pgbench
>> simple.
>> These two new test variants, gaussian and exponential, are not that
>> special that
>> they'd deserve to be included in the program itself.
>
> Well, I add only two options, and they are major distribution that are seen
> in real database system than uniform distiribution. I'm afraid, I think you
> are too worried and it will not be added hundreds of options. And pgbench is
> still simple.
>
>
>> pgbench already has a mechanism for running custom scripts, in which you
>> can
>> specify whatever workload you want. Let's use that. If it's missing
>> something you
>> need to specify the workload you want, let's enhance the script language.
>
> I have not seen user who is using pgbench custom script very much. And
> gaussian and exponential distribution are much better to measure the real
> system perfomance, so I'd like to use it command option. In now pgbench, we
> can only measure about database size, but it isn't realistic situation. We
> want to forcast the required system from calculating the size of hot spot or
> distirbution of access pettern.
>
> I'd realy like to include it on my heart:)  Please...

I have no strong opinion about the command-line option for gaussian,
but I think that we should focus on \setrandom gaussian first. Even
after that's committed, we can implement that commnand-line option
later if many people think that's necessary.

Regards,

-- 
Fujii Masao