public inbox for [email protected]  
help / color / mirror / Atom feed
From: Shinya Kato <[email protected]>
To: Fujii Masao <[email protected]>
Cc: PostgreSQL Hackers <[email protected]>
Subject: Re: pg_stat_replication.*_lag sometimes shows NULL during active replication
Date: Sat, 21 Mar 2026 11:04:32 +0900
Message-ID: <CAOzEurSAvOf-vxzn9yQaCipgD6bSr4ncoTYjFceAPDO5fzMNNw@mail.gmail.com> (raw)
In-Reply-To: <CAHGQGwGLUXmjC1+A1fzg-ynP1pdKC-0yfmLYcnnu4YJSEDnuQw@mail.gmail.com>
References: <CAOzEurTzcUrEzrH97DD7+Yz=HGPU81kzWQonKZvqBwYhx2G9_A@mail.gmail.com>
	<CAHGQGwE=kyQ+YnGPn8zpZ959+3ywg8OR_Nu__uXxxuE0E+Y_Zg@mail.gmail.com>
	<CAOzEurRGiGE2Dfe+ySpb=+93ku=7ZC6RgAbHtLC6Xsq3g2XexA@mail.gmail.com>
	<CAHGQGwH2h_R7FWPvEs3+NWLwHZoj9r96tUyRKi5haqxMc6FXiQ@mail.gmail.com>
	<CAOzEurQiP3uebd1GMiC1Dzf5VJwF4ZBEpJ6QYQFE6Y+rVjxqNA@mail.gmail.com>
	<CAHGQGwEmMBBAE0RG-R3_LacfT4fbB55qGE6n9O5mNwrqvbNBtw@mail.gmail.com>
	<CAOzEurRF+OWcMZpfE=NV_Wcm6CFFGOnuxC6L9WWCjOMN0_eZMQ@mail.gmail.com>
	<CAHGQGwGPg20Rw2PydBDXiKHgn55s--E14-qRy7t3M+DHreCJww@mail.gmail.com>
	<CAOzEurSDzFsRXjofhq7mbNgoL8HaVbNeEhWBm7m9_K2ZNQnaBw@mail.gmail.com>
	<CAHGQGwFzg9J_z71kwnjXOxaoO3upMW8RdT4ieE8MBLq6h-ojZg@mail.gmail.com>
	<CAOzEurRV117N2neo1N_O+xWPv=-R7qou+i7k-h79JjTP9sO1Fg@mail.gmail.com>
	<CAHGQGwGLUXmjC1+A1fzg-ynP1pdKC-0yfmLYcnnu4YJSEDnuQw@mail.gmail.com>

On Fri, Mar 20, 2026 at 2:13 AM Fujii Masao <[email protected]> wrote:
> I think the issue occurs when the positions in the first message point to
> the same LSN (e.g., 0/030D5230), and the second message reports the same but
> larger LSN (e.g., 0/030D52E0).

Thanks for the explanation!

> I've updated the patch to address this. It removes fullyAppliedLastTime,
> tracks the positions from the previous reply, and clears the lag values only
> when the positions remain unchanged across two consecutive messages.
>
> Patch attached. Could you test and review this updated patch?

The patch works properly. I think it looks nice to me, except for the
typo I sent in the previous message.


-- 
Best regards,
Shinya Kato
NTT OSS Center





view thread (21+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: Re: pg_stat_replication.*_lag sometimes shows NULL during active replication
  In-Reply-To: <CAOzEurSAvOf-vxzn9yQaCipgD6bSr4ncoTYjFceAPDO5fzMNNw@mail.gmail.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox