Re: PostgreSQL 18 GA press release draft

On Wed, Sep 10, 2025 at 10:13 AM Jonathan S. Katz <jkatz@postgresql.org> wrote:

> PostgreSQL 18 also supports using x86 AVX-512 instructions for CRC32 calculations, which are used in page checksums
andare also available in the new
[`crc32`](https://www.postgresql.org/docs/18/functions-binarystring.html#FUNCTIONS-BINARYSTRING-OTHER)function. 

Hi Jon,

The checksum stored in the page header is not actually a CRC but
something else entirely. WAL records are a convenient example of
something that uses CRC.

Also, CRC32 is not hardware accelerated, only CRC32C is. We have two
SQL-callable functions.  To avoid confusion maybe they can be omitted
from this longer-than-usual announcement -- they seem like a niche
feature anyway.

--
John Naylor
Amazon Web Services