Re: Fails to work on live images due to fsync() on pg_commit_ts before doing any write there

On Tue, 07 Nov 2017, Andres Freund wrote:
> > The time
> > to get a fix there is also relatively long. If they work on a fix quickly,
> > it might get merged for Linux 3.15 which we will not have in Kali before
> > 2-3 months too.
>
> So the same timeframe as a new PG release?

Yes, looks like so.

> > For now, I have added an ugly work-around that creates a file in the
> > pg_commit_ts directory (and immediately drops it) just before starting
> > PostgreSQL:
> > http://git.kali.org/gitweb/?p=packages/kali-defaults.git;a=commitdiff;h=f4287fd774f8d0686ba919f57355215a6b9633e3
>
> Hm. The comment:
> + # Ensure the directory is copied over in the tmpfs
> suggests that the overlay isn't persistent? If that's indeed the case,
> you could just disable fsyncs alltogether.

Well, it's the case by default with no persistence. But some users enable
persistence and then it's no longer a tmpfs which is used.

The problem also exists when you enable persistence but start with an
empty upper layer so disabling fsyncs is not really an option.

Cheers,
--
Raphaël Hertzog ◈ Debian Developer

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