How to perform parallel execution on the `cstore_fdw` partition table ?

Question

How to perform parallel execution on the `cstore_fdw` partition table ?

suuuch opened this issue 7 years ago · 4 comments

I was use cstore_fdw, and I created 20 partition table ,when i query the partition table ,I realize the query plan did not show the parallel.But when use the normal table ,the parallel is worked.

This make me confuse. Is there anyone can help?

Answer 1 · 2018-01-29T09:31:10.000Z

hi @suuuch
unfortunately cstore_fdw does not support parallel scans yet. It looks like postgresql is not using parallel scan when one partition does not support paralel execution (needs verification).

Answer 2 · 2018-11-30T18:46:59.000Z

Any plans to address this issue?

Answer 3 · 2018-12-01T00:02:38.000Z

A colleague of mine tried this on partitioned cstore tables and said it's working, making things faster: https://gist.github.com/masayuki038/6820f551f1a6d4e1ec7b3929ffad35ad

Answer 4 · 2018-12-03T21:08:15.000Z

Basically, he just set ForeignScanParallelSafe to true. That is nice, but I would like to hear why wasn't it safe in the first place, @mtuncer ?