Hi Tom,
Thanks for the feedback and insights. I will follow your advice, observe and report if I find something which could
explainthis behavior
Regard
Arnd
> Am 06.02.2024 um 03:18 schrieb Tom Lane <tgl@sss.pgh.pa.us>:
>
> Arnd Baranowski <baranowski@oculeus.com> writes:
>> Correction fsync is „On" and the wal_sync_method is set to „open_datasync“
>
> That's what they should be.
>
> I tried to reproduce this by selecting "Restart..." immediately after
> creating/populating a table on my own MacBook running Sonoma 14.3.
> After the reboot, the table was there with the expected contents.
> Now, this test doesn't actually prove a heck of a lot about PG's
> crash recovery, because I see in the postmaster log
>
> 2024-02-05 21:00:30.322 EST [1148] LOG: database system was shut down at 2024-02-05 20:58:46 EST
> 2024-02-05 21:00:30.327 EST [1144] LOG: database system is ready to accept connections
>
> which indicates that Postgres had time to perform a clean shutdown
> before the system rebooted. (That is the expected scenario for an
> OS reboot, assuming that the kernel delivers us SIGTERM as it's
> required to do by POSIX and then gives us enough time to nail the
> windows shut, which it's not required to do.)
>
> The facts as you've presented them indicate that (1) checkpoints
> weren't working, (2) we didn't get SIGTERM at system shutdown, *and*
> (3) WAL wasn't written out to disk as it's supposed to be. It's
> a bit hard to credit that so many things are broken and nobody has
> noticed. I'm inclined to wonder if something is wrong with your
> disk drive.
>
> It would be interesting to know what appears in the first few lines
> of your postmaster log after a data-losing restart. Also, try
> running with log_checkpoints = on for awhile, and see if there are
> log entries claiming successful checkpoint completion.
>
> A different line of thought is that maybe the corruption is happening
> because you have two postmasters started in the same data directory.
> We have interlocks that are supposed to defend against that, but it'd
> be a lot easier to credit that those aren't working than that all the
> rest of this stuff broke.
>
> regards, tom lane
