Re: Experimental evaluation of PostgreSQL's query optimizer
| От | Simon Riggs |
|---|---|
| Тема | Re: Experimental evaluation of PostgreSQL's query optimizer |
| Дата | |
| Msg-id | CANP8+jLtpYhzSPt8PJooCrhcWpLMLMrGO9Fy78JXf-ba6Y5SEA@mail.gmail.com обсуждение исходный текст |
| Ответ на | Experimental evaluation of PostgreSQL's query optimizer (Viktor Leis <leis@in.tum.de>) |
| Список | pgsql-hackers |
On 16 December 2015 at 09:51, Viktor Leis <leis@in.tum.de> wrote:
--
Hi,
We have recently performed an experimental evaluation of PostgreSQL's
query optimizer. For example, we measured the contributions of
cardinality estimation and the cost model on the overall query
performance. You can download the resulting paper here:
http://www.vldb.org/pvldb/vol9/p204-leis.pdf
Thank you, an excellent contribution.
Some findings:
1. Perhaps unsurprisingly, we found that cardinality
estimation is the biggest problem in query optimization.
2. The quality of Postgres' cardinality estimates is not generally worse
than that of the major commerical systems.
Good to hear, though we have found problems there that alter plan selection adversely for TPC-H with the current optimizer. We have some improvements which may be in the next release.
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
В списке pgsql-hackers по дате отправления: