Re: pg_waldump stucks with options --follow or -f and --stats or -z

On Fri, Nov 26, 2021 at 11:50 AM Michael Paquier <michael@paquier.xyz> wrote:
>
> On Sat, Nov 20, 2021 at 11:46:35AM +0530, Bharath Rupireddy wrote:
> > Thanks. Here's the v3 patch, a much simpler one. Please review it.
>
> +   pqsignal(SIGINT, SignalHandlerForTermination);
> +   pqsignal(SIGTERM, SignalHandlerForTermination);
> +   pqsignal(SIGQUIT, SignalHandlerForTermination);
> FWIW, I think that we should do this stuff only on SIGINT.  I would
> imagine that this behavior becomes handy mainly when one wishes to
> Ctrl+C the terminal running pg_waldump but still get some
> information.

Done.

>      XLogDumpCountRecord(&config, &stats, xlogreader_state);
> +    stats.endptr = xlogreader_state->currRecPtr;
> Isn't what you are looking for here EndRecPtr rather than currRecPtr,
> to track the end of the last record read?

You are right.

> +    When <option>--follow</option> is used with <option>--stats</option> and
> +    the <application>pg_waldump</application> is terminated or interrupted
> +    with signal <systemitem>SIGINT</systemitem> or <systemitem>SIGTERM</systemitem>
> +    or <systemitem>SIGQUIT</systemitem>, the summary statistics computed
> +    as of the termination will be displayed.
> This description is not completely correct, as the set of stats would
> show up only by using --stats, in non-quiet mode.  Rather than
> describing this behavior at the end of the docs, I think that it would
> be better to add a new paragraph in the description of --stats.

Done.

PSA v4 patch.

Regards,
Bharath Rupireddy.