| From: | John Naylor <johncnaylorls(at)gmail(dot)com> |
|---|---|
| To: | David Rowley <dgrowleyml(at)gmail(dot)com> |
| Cc: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, PostgreSQL Developers <pgsql-hackers(at)lists(dot)postgresql(dot)org> |
| Subject: | Re: Incorrect CHUNKHDRSZ in nodeAgg.c |
| Date: | 2025-01-04 02:24:02 |
| Message-ID: | CANWCAZa5HzVH0uJ4XSJFatAtaGK7iND7JoJE9Pyd6b9SM_9=vA@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Thu, Jan 2, 2025 at 7:24 AM David Rowley <dgrowleyml(at)gmail(dot)com> wrote:
>
> Bump wouldn't work due to the SH_FREE() in SH_GROW() when resizing the
> table. If sizeof(TupleHashEntryData) were a power-of-two, then there'd
> be no wastage as the hash table always has a power-of-two bucket count
> and two powers-of-two multiplied are always a power-of-two value.
> Unfortunately, TupleHashEntryData is 24 bytes and I don't see any easy
> way to shrink it to 16 bytes.
FYI, there is a proposal for that at
https://www.postgresql.org/message-id/817d244237878cebdff0bc363718feaf49a1ea7d.camel@j-davis.com
--
John Naylor
Amazon Web Services
| From | Date | Subject | |
|---|---|---|---|
| Next Message | wenhui qiu | 2025-01-04 03:41:24 | Re: POC: track vacuum/analyze cumulative time per relation |
| Previous Message | Matthias van de Meent | 2025-01-04 01:12:58 | Re: Revisiting {CREATE INDEX, REINDEX} CONCURRENTLY improvements |