Re: Slow performance with 9.3-110x JDBC 4

Thank you very much for your help and explanations.

Indeed, the Lachezar's recommendation  (jdbc:postgresql://localhost/database?protocolVersion=2) restores the speed: 190413 ms with jdbc-9.3.1101 and postgresql 9.3.4.

As I used bytea and due to change since postgresql 9.0 for handling them (bytea_output parameter), my programs only work with  jdbc-9.3.1101 (and no longer with jdbc-8.4-703).

So, I must use 9.3.1101. However, what  does the sentence "I was recommending that for testing purposes only" by Lachezar means ? How to increase performance of server side prepared statements ?

Le Vendredi 28 mars 2014 10h50, Lachezar Dobrev <l(dot)dobrev(at)gmail(dot)com> a écrit :

  For the record: I was recommending that for testing purposes only, to check if the reduced performance is related to protocol version (I believe there is a significant change it might).

2014-03-27 21:52 GMT+02:00 Dave Cramer <davecramer(at)gmail(dot)com>:

I wanted to avoid that recommendation, but since it is out there. protocolVersion reverts to the same protocol as 8.4 uses which does not use server side prepared statements
>
>
>And I would expect it to speed up, or at least be the same as 8.4.7
>
>
>Dave
>
>
>www.credativ.ca
>
>
>
>
>On Thu, Mar 27, 2014 at 1:45 PM, Edson Richter <edsonrichter(at)hotmail(dot)com> wrote:
>
>Em 27/03/2014 13:58, Lachezar Dobrev escreveu:
>>
>>You might want to do the same tests after adding ?protocolVersion=2
to the connection URL. i.e.: jdbc:postgresql://localhost/database?protocolVersion=2 2014-03-27 15:35 GMT+02:00 ChatPristi <cchristo_0899(at)yahoo(dot)fr>:
>>>Dear All, I have a java program that does bulk insertions (with transactions and
PreparedStatements) in a postgresql database. I have a performance divided
between two and four when using 9.3-1100 JDBC4 and 9.3-1101 in comparison
with postgresql-8.4-703 JDBC4 independently of postgresql version. Time(ms) PG 8.4.7 9.3.4
Driver
8.4-703 193390 188379
9.3.1101 349404 344344 Does anybody else saw such a difference ? What reasons can explain it ? Another point, is that the bulk insertions are prerformed by parallel
processes and 9.3-110x JDBC4 drivers appear to scale poorly. Thanks for any help.
What to expect from "protocolVersoin=2"?
>>Speed up or down?
>>
>>Edson
>>
>>
>>--
>>
>>
>>Edson Carlos Ericksson Richter
>>Sistemas para Bibliotecas, Escolinhas Infantis
>>Projetos sob medida para sua empresa
>>Celular: (51) 9318-9766
>>(51) 8585-0796
>>"A mente que se abre a uma nova ideia jamais voltará ao seu tamanho original"
>>- Albert Einstein
>>
>