Обсуждение: Display is_prev_bucket_same_wrt of xl_hash_squeeze_page

Hi hackers!

While doing some xlog-related task at my job I noticed that pg_waldump
utility does not display `is_prev_bucket_same_wrt` of
xl_hash_squeeze_page record. I had to patch pg_waldump to fix the
issue, because I use pg_waldump output of vanilla pg to cross-check my
patches (in our closed-source pg-related project).

PFA fixing issue.


-- 
Best regards,
Kirill Reshke

On Wed, Sep 10, 2025 at 06:28:10PM +0500, Kirill Reshke wrote:
> While doing some xlog-related task at my job I noticed that pg_waldump
> utility does not display `is_prev_bucket_same_wrt` of
> xl_hash_squeeze_page record. I had to patch pg_waldump to fix the
> issue, because I use pg_waldump output of vanilla pg to cross-check my
> patches (in our closed-source pg-related project).

Good idea.

We are still missing the offsets in xl_hash_vacuum_one_page, which
would lead to a longer output, with perhaps less value in in.

How about old_bucket_flag and new_bucket_flag in
xl_hash_split_allocate_page, as well as procid in
xl_hash_init_meta_page?  While we are looking at this area, we may as
well close the gap in the output produced.
--
Michael

HI, thanks for looking into this.

On Thu, 11 Sept 2025 at 05:54, Michael Paquier <michael@paquier.xyz> wrote:

> We are still missing the offsets in xl_hash_vacuum_one_page, which
> would lead to a longer output, with perhaps less value in in.

Yes. I guess we might want to implement this to keep things in sync:
we display dead/redirected tuple offsets in PRUNE VACUUM SCAN output
already, so maybe just display here too, this is also vacuum.

> How about old_bucket_flag and new_bucket_flag in
> xl_hash_split_allocate_page, as well as procid in
> xl_hash_init_meta_page?  While we are looking at this area, we may as
> well close the gap in the output produced.


Sure

PFA v2.

-- 
Best regards,
Kirill Reshke