Re: Zstandard support for toast compression

On Wed, May 18, 2022 at 9:47 PM Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>
> I do understand that Zstandard is a good compression algorithm, and if
> we had an extensibility mechanism here where one of the four possible
> bit patterns then indicates that the next byte (or two or four) stores
> the real algorithm type, then what about adding Zstandard that way
> instead of consuming one of our four primary bit patterns? That way
> we'd have this option for people who want it, but we'd have more
> options for the future instead of fewer.
>
> i.e. something like:
>
> 00 = PGLZ
> 01 = LZ4
> 10 = reserved for future emergencies
> 11 = extended header with additional type byte (1 of 256 possible
> values reserved for Zstandard)
>

+1 for such an extensible mechanism if we decide to go with Zstandard
compression algorithm. To decide that won't it make sense to see some
numbers as Michael already has a patch for the new algorithm?

--
With Regards,
Amit Kapila.