Hi Manni!
On Mon, 9 Mar 2026 at 16:31, Manni Wood <manni.wood@enterprisedb.com> wrote:
>
> I was being too brief.
>
> The benchmarks I shared were absolutely with lz4 compiled in and 'default_toast_compression = lz4' set in
postgresql.conffor every postgres instance I tested with. (Furthermore, I ran `show default_toast_compression` via
`psql`on each postgres instance to be sure 'default_toast_compression = lz4' was really set!)
>
> Also, all were compiled using meson using `debugoptimized` which results in `-g -O2`.
>
> So those are the benchmarks that I shared.
Thanks for the clarification.
> OK, so my final question, hopefully clarified: If I run additional benchmarks where pglz is used for
default_toast_compression,is it enough to use the instances I have already compiled with lz4 in them, but with
'default_toast_compression= pglz` explicitly set in postgresql.conf in a brand new data dir created by initdb? (In
otherwords, existing data dir deleted, then initdb run to make a new data dir, then postgresql.conf edited to ensure
'default_toast_compression= pglz` explicitly set, then and only then starting up the cluster for the first time... and
finallyverifying via `show default_toast_compression` for good measure.)
>
> Or should I re-compile with the lz4-is-now-the-default commit completely excised?
Yes, it is clear now; thanks. You don't need to compile without the
lz4-is-now-the-default commit. You can compile with lz4 commit and set
the 'default_toast_compression = pglz' in the postgresql.conf like you
said. This should be enough.
--
Regards,
Nazir Bilal Yavuz
Microsoft
