Horton
Menu

Re: Reduce build times of pg_trgm GIN indexes

David Geier <geidav.pg@gmail.com>

View thread
From: David Geier <geidav.pg@gmail.com>
To: Matthias van de Meent <boekewurm+postgres@gmail.com>
Cc: Heikki Linnakangas <hlinnaka@iki.fi>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2026-03-03T17:31:51Z
Lists: pgsql-hackers

Attachments

> Attached are the patches rebased on latest master.
> 
> I've removed the ASCII fast-path patch 0006 as it turned out to be more
> complicated to make work than expected.
> 
> I kept the radix sort patch because it gives a decent speedup but I
> would like to focus for now on getting patches 0001 - 0004 merged.
> They're all simple and, the way I see it, uncontroversial.
> 
> I remeasured the savings of 0001 - 0004, which comes on top of the
> already committed patch that inlined the comparison function, which gave
> another ~5%:
> 
> Data set            | Patched (ms) | Master (ms)  | Speedup
> --------------------|--------------|--------------|----------
> movies(plot)        |   8,058      |  10,311      | 1.27x
> lineitem(l_comment) | 223,233      | 256,986      | 1.19x
> 
> I've also registered the change at the commit fest, see
> https://commitfest.postgresql.org/patch/6418/.

Attached is v5 that removes an incorrect assertion from the radix sort code.

--
David Geier

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Change PointerGetDatum() back to a macro

  2. Replace deprecated StaticAssertStmt() with StaticAssertDecl()

  3. Optimize sorting and deduplicating trigrams

  4. Optimize sort and deduplication in ginExtractEntries()

  5. Inline ginCompareAttEntries for speed