po 10. 2. 2020 v 18:20 odesÃlatel Konstantin Knizhnik < k.knizh...@postgrespro.ru> napsal:
> I have done some performance comparisons. > First of all I failed to run vectorized version of Q1 with master branch > of your repository and > PG9_6_STABLE branch of Postgres: > > NOTICE: query can't be vectorized > DETAIL: Non plain agg is not supported > > I have to switch to pg96 branch. > > Results (seconds) of Q1 execution are the following: > > max_parallel_workers_per_gather > PG9_6, enable_vectorize_engine=off > PG9_6, enable_vectorize_engine=on > master (jit=on) > 0 > 36 > 20 > 10 > 4 > 10 > - > 5 > > > I failed to run parallel version of Q1 with enable_vectorize_engine=on > because of the same error: "Non plain agg is not supported" > > > So looks like PG-13 provides significant advantages in OLAP queries > comparing with 9.6! > Definitely it doesn't mean that vectorized executor is not needed for new > version of Postgres. > Once been ported, I expect that it should provide comparable improvement > of performance. > > But in any case I think that vectorized executor makes sense only been > combine with columnar store. > +1 Pavel > > > -- > Konstantin Knizhnik > Postgres Professional: http://www.postgrespro.com > The Russian Postgres Company > >
