Re: [Postgres-xc-general] JDBC driver for 0.9.4

[Michael P. <mic...@gm...>]

There is also something I noticed with the way data is distributed among
nodes.
Now all the table are using the warehouse ID (this looks exactly like TPC-C
benchmark test) as a distribution key.
If you let the benchmark running like that by default with only 1 warehouse,
you will finish with all your data located on the same node, resulting in
bad performance.

If you are looking for performance tests, you may need to use far more
warehouses (don't know, 20~100) or a different distribution key, but
regarding all the tables warehouse ID is definitely the best distribution
key. So, I would recommend to use a high number of warehouses and distribute
all the tables with warehouse ID as distribution key.
item table does not use warehouse ID, so it is better to replicate this
table among nodes.

On Mon, May 30, 2011 at 10:50 AM, Michael Paquier <mic...@gm...
> wrote:

> Hi,
>
> I tested the benchmark with latest head code, and it looks to work on my
> side without crashing.
> Respecting what you said in your previous email and what is written in
> README.
> #Create database
> createdb test
> #Create tables
> ./runSQL.sh postgres.properties sqlTableCreates
> #Data generation
> ./loadData.sh postgres.properties numWarehouses 1
> #Index creation
> ./runSQL.sh postgres.properties sqlIndexCreates
> #To launch test terminal
> ./runBenchmark.sh postgres.properties
>
> With the following properties
> driver=org.postgresql.Driver
> conn=jdbc:postgresql://localhost:5432/test
>
> user=******
> password=*****
>
> I found in the logs some errors such as:
> LOG:  execute <unnamed>: SELECT c_discount, c_last, c_credit, w_tax  FROM
> customer, warehouse WHERE w_id = $1 AND w_id = c_w_id AND c_d_id = $2 AND
> c_id = $3
> DETAIL:  parameters: $1 = '1', $2 = '10', $3 = '1549'
> ERROR:  bind message supplies 3 parameters, but prepared statement ""
> requires 0
>
> But this is expected as XC does not yet manage multi-prepared queries and
> BenchmarkSQL looks to use it.
> Btw, this is enough to get some results.
>
> Also, I am wondering about this error you got:
>
> LOG:  could not create IPv6 socket: Address family not supported by
> protocol
> I am using here only IPv4 protocol.
> --
> Michael Paquier
> http://michael.otacoo.com
>


Regards,
-- 
Michael Paquier
http://michael.otacoo.com