Re: BUG #17449: Disk space not released

On Mon, May 30, 2022, 7:40 AM Giorgio Saviane <gsaviane(at)gmail(dot)com> wrote:

> >>>
> >>> > Despite any attempt
> >>> > of full vacuum the discrepancy remained the same. I suspect that
> Postgres
> >>> > started leaking disk space. I could see many 1Gb files with a
> timestamp of
> >>> > two months back in time in the postgres data folder.
> >
> >
> > If the database suffers a crash (or immediate shutdown) in the middle of
> something like VACUUM FULL or CLUSTER, it might leave orphaned in-process
> files such as the ones you describe behind and have no way to know to clean
> them up. The knowledge about what it was working on just before the crash
> was lost in the crash.
> >
> > Files not touched in 2 months and also not referenced in
> pg_class.relfilenode are almost certainly such orphaned files and could,
> with extreme nervousness, be cleaned up by hand. Especially if the
> human-readable log files support a crash having happened at that time.
>
> That was not the case. The server has been running seamlessly since I
> rebuilt the master.
>

But as i understand it, you rebuilt the master as a response to the
problem, so the time period in question is before the rebuild, not after.

Cheers,

Jeff