Re: Initdb-time block size specification

On 6/30/23 23:11, Andres Freund wrote:
> ...
>
> If we really wanted to do this - but I don't think we do - I'd argue for
> working on the buildsystem support to build the postgres binary multiple
> times, for 4, 8, 16 kB BLCKSZ and having a wrapper postgres binary that just
> exec's the relevant "real" binary based on the pg_control value. I really
> don't see us ever wanting to make BLCKSZ runtime configurable within one
> postgres binary. There's just too much intrinsic overhead associated with
> that.
>

I don't quite understand why we shouldn't do this (or at least try to).
IMO the benefits of using smaller blocks were substantial (especially
for 4kB, most likely due matching the internal SSD page size). The other
benefits (reducing WAL volume) seem rather interesting too.

Sure, there are challenges (e.g. the overhead due to making it dynamic).
No doubt about that.

regards

--
Tomas Vondra
EnterpriseDB: http://www.enterprisedb.com
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