Re: Queries containing ORDER BY and LIMIT started to work slowly

On Tue, Aug 29, 2023 at 3:57 PM Rondat Flyag <rondatflyag@yandex.ru> wrote:

> I took the dump just to store it on another storage (external HDD). I
> didn't do anything with it.
>
> 29.08.2023, 21:42, "Jeff Janes" <jeff.janes@gmail.com>:
>
>
>
> On Tue, Aug 29, 2023 at 1:47 PM Rondat Flyag <rondatflyag@yandex.ru>
> wrote:
>
> I have a legacy system that uses `Posgresql 9.6` and `Ubuntu 16.04`.
> Everything was fine several days ago even with standard Postgresql
> settings. I dumped a database with the compression option (maximum
> compression level -Z 9) in order to have a smaller size (`pg_dump
> --compress=9 database_name > database_name.sql`). After that I got a lot of
> problems.
>
>
> You describe taking a dump of the database, but don't describe doing
> anything with it.  Did you replace your system with one restored from that
> dump?  If so, did vacuum and analyze afterwards?
>
> Cheers,
>
> Jeff
>
>
Since this is a very old system and backups are fairly I/O intensive, it is
possible you have a disk going bad?  Sometimes after doing a bunch of I/O
on an old disk, it will accelerate its decline.  You could be about to lose
it altogether.