Re: [Postgres-xc-developers] A question on DBT1 performance

[xiong w. <wan...@gm...>]

Hi, Michael

Thank you for your advice.


2010/11/25 Michael Paquier <mic...@gm...>

> I have a comment about some of the parameters you are using with DBT-1.
>
> #eu
> 1500
> #eu/min
> 1000
>
> The current algorithm of DBT-1 just recognizes multiple numbers when
> calculating ramp-up value.
> For example, if you set eu at 1500, you have to set eu/min at 500, 750 or
> 1500 to have a ramp up time of 1, 2 or 3 minutes.
> If you don't do that ramp up is set I set at 0, what might give you wrong
> results.
>
> Then, you seem still have a lot of idle CPU.
> You should increase eu by 15%~20% to saturate your cpu.
>
> I would recommend to set eu at 2000~2200 for a eu/min at 500~550.
>
I will test it again later.


>
> I can also see in your results that method 1 is using in total 2
> connections between the loaders and coordinators.
> Method 2 is using 4 connections.
> I think you did so but... Did you include for method 2 the results of
> loader1-coordinator1 + loader1-coordinator2 for loader1 results?
> Same for loader2?
>
As I know one loader can get one DBT1 result. As you told, a coordinator
should get one DBT1 result beacuse you said I should use
loader1-coordinator1 + loader1-coordinator2 as the result of method2. I don'
t know how can I get DBT1 results according to coordinator.

Thanks again.

Regards,
Benny

>
> --
> Michael Paquier
> http://michaelpq.users.sourceforge.net
>
>