Re: n_ins_since_vacuum stats for aborted transactions

From: David Rowley <dgrowleyml(at)gmail(dot)com>
To: Sami Imseih <samimseih(at)gmail(dot)com>
Cc: "David G(dot) Johnston" <david(dot)g(dot)johnston(at)gmail(dot)com>, Mark Dilger <mark(dot)dilger(at)enterprisedb(dot)com>, Euler Taveira <euler(at)eulerto(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: n_ins_since_vacuum stats for aborted transactions
Date: 2025-04-18 04:13:02
Message-ID: CAApHDvopVdM7jE32i+i_EVV9Gseqq4kz7cJad8hx9ktSV+NREw@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Sat, 12 Apr 2025 at 07:33, Sami Imseih <samimseih(at)gmail(dot)com> wrote:
> What do you think of the attached?

I looked at the v3 patch and I'm having trouble getting excited about it.

I'd say this part is misleading:

@@ -3956,7 +3961,8 @@ description | Waiting for a newly initialized
WAL file to reach durable storage
<structfield>n_dead_tup</structfield> <type>bigint</type>
</para>
<para>
- Estimated number of dead rows
+ Estimated number of dead rows (updated by committed transactions, or by
+ <command>VACUUM</command> and <command>VACUUM FULL</command>)
</para></entry>

An aborted insert will contribute to that counter, but that's not mentioned.

Would it be ok just to adjust n_mod_since_analyze's "Estimated number
of rows modified since this table was last analyzed" and inject "by
committed transactions" after "modified", then call it a day?

David

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Amit Kapila 2025-04-18 04:28:57 Re: Fix slot synchronization with two_phase decoding enabled
Previous Message Thomas Munro 2025-04-18 01:27:35 Re: Changing shared_buffers without restart