Re: Preventing free space from being reused

2021-02-14 Thread Noah Bergbauer
>I would suggest to take a look at the BRIN opclass multi-minmax currently in development. Thank you, this does look like it could help a lot with BRIN performance in this situation! But again, if index performance alone was the only issue, then I would simply accept the space overhead and switch

Re: Preventing free space from being reused

2021-02-13 Thread John Naylor
On Fri, Feb 12, 2021 at 6:21 PM Noah Bergbauer wrote: > > A btree index on the same column is 700x the size of BRIN, or 10% of relation itself. It does not perform significantly better than BRIN. The issue here is twofold: not only does slotting these tuples into older pages significantly reduce t

Re: Preventing free space from being reused

2021-02-12 Thread Noah Bergbauer
> (My reaction to your previous thread was that it was simply a question > of blindly insisting on using BRIN indexes for a case that they're quite > badly adapted to. The better answer is to not use BRIN.) Apologies, perhaps I am completely misunderstanding the motivation for BRIN? >From the do

Re: Preventing free space from being reused

2021-02-12 Thread Tom Lane
Noah Bergbauer writes: > I am working on a project where I do not want Postgres to reuse free space > in old pages (see > https://www.postgresql.org/message-id/flat/CABjy%2BRhbFu_Hs8ZEiOzaPaJSGB9jqFF0gDU5gtwCLiurG3NLjQ%40mail.gmail.com > for details). I found that the HEAP_INSERT_SKIP_FSM flag acc

Preventing free space from being reused

2021-02-12 Thread Noah Bergbauer
Hello, I am working on a project where I do not want Postgres to reuse free space in old pages (see https://www.postgresql.org/message-id/flat/CABjy%2BRhbFu_Hs8ZEiOzaPaJSGB9jqFF0gDU5gtwCLiurG3NLjQ%40mail.gmail.com for details). I found that the HEAP_INSERT_SKIP_FSM flag accomplishes this. For a lo