Re: Performance comparison between Postgres and Greenplum

,--- You/Suvankar (Wed, 15 Jul 2009 18:32:12 +0530) ----*
| Yes, I have got 2 segments and a master host. So, in a way processing
| should be faster in Greenplum.

No, it should not: it all depends on your data, SQL statements and
setup.

In my own experiments, with small amounts of stored data, PostgreSQL
beats Greenplum, which doesn't surprise me a bit.

You need to know where most of the execution time goes -- maybe to
sorting?  And sorting in Greenplum, isn't it done on one machine, the
master host?  Why would that be faster than in PostgreSQL?
|
| For other queries though, results are satisfactory or at least comparable,
| like-
|
| select distinct so_no, serial_no from observation_all;
| in postgres it takes - 1404.238 ms
| in gp it takes - 1217.283 ms

No surprise here: the data is picked by multiple segment hosts and
never sorted on the master.

-- Alex -- alex-goncharov@comcast.net --