Re: Can't get Dell PE T420 (Perc H710) perform better than a MacMini with PostgreSQL

Just looking at the 2 B_2 queries, I'm curious as to why is the execution
plan different between the 2 machines. Is the optimiser stats updated on
both databases?

Regards,
Wei Shan

On 1 April 2015 at 22:32, Aidan Van Dyk <aidan(at)highrise(dot)ca> wrote:

> On Wed, Apr 1, 2015 at 9:56 AM, Pietro Pugni <pietro(dot)pugni(at)gmail(dot)com>
> wrote:
>
>
>> *Now let’s propose some query profiling times.*
>>
>> B type set are transactions, so it's impossible for me to post EXPLAIN
>> ANALYZE results. I've extracted two querys from a single transactions
>> and executed the twos on both system. Here are the results:
>>
>> *T420*
>>
>> Query B_1 [55999.649 ms + 0.639 ms] http://explain.depesz.com/s/LbM
>>
>> Query B_2 [95664.832 ms + 0.523 ms] http://explain.depesz.com/s/v06
>>
>> *MacMini*
>>
>> Query B_1 [56315.614 ms] http://explain.depesz.com/s/uZTx
>>
>> Query B_2 [44890.813 ms] http://explain.depesz.com/s/y7Dk
>>
>
> Looking at the 2 B_2 queries (since they are so drastically different),
> the in-memory quicksorts stand out on the Dell as being *drastically*
> slower than the disk-based sorts on your mac-mini....
>
>

--
Regards,
Ang Wei Shan