Re: Infinite loop in XLogPageRead() on standby

Hi Kyotaro,

Oh, now I understand what you mean. Is the retry supposed to happen only
when we are reading the very first page from the WAL file?

On Wed, 6 Mar 2024 at 09:57, Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com>
wrote:

>
> xlogrecovery.c:
> @@ -3460,8 +3490,10 @@ retry:
> * responsible for the validation.
> */
> if (StandbyMode &&
> + targetPagePtr % 0x100000 == 0 &&
> !XLogReaderValidatePageHeader(xlogreader, targetPagePtr,
> readBuf))
> {
>
>
Hmm, I think you meant to use wal_segment_size, because 0x100000 is just
1MB. As a result, currently it works for you by accident.

> Thus, I managed to reproduce precisely the same situation as you
> described utilizing your script with modifications and some core
> tweaks, and with the change above, I saw that the behavior was
> fixed. However, for reasons unclear to me, it shows another issue, and
> I am running out of time and need more caffeine. I'll continue
> investigating this tomorrow.
>

Thank you for spending your time on it!

--
Regards,
--
Alexander Kukushkin