On Thu, Apr 10, 2025 at 7:35 AM Andres Freund wrote:
> 1) Increase distance by * 2 + read_size on a miss
>
>This would help us to increase with distance = 1, where * 2 only increases
>distance by 1, just as -1 obviously reduces it by 1.
>
>It'd also somewhat address the over-weighing o
Hi,
On 2025-04-09 19:17:00 +1200, Thomas Munro wrote:
> One weird issue, not just with reordering, is that read_stream.c's
> distance cools off too easily with some simple test patterns. Start
> at 1, double on miss, subtract one on hit, repeat, and you can be
> trapped alternating between 1 and
Here is a more fleshed out version of this concept patch, now that we
have lots of streams wired up to try it with. Bitmap Heap Scan seemed
to be a good candidate.
postgres=# create table t (a int unique, b int unique);
CREATE TABLE
postgres=# insert into t select generate_series(1, 10),
gene
On Tue, Apr 9, 2024 at 12:19 AM Thomas Munro wrote:
> This idea is due to Robert Haas, who complained that he feared that
> the streaming I/O API already worked like this. It doesn't, but it
> could! Here is a concept patch to try it out.
Oh, no, it's all my fault!
My favorite part of this pat
