Re: Performance degradation after upgrading from 9.5 to 14

1) How did you upgrade? pg_dump or pg_upgrade?

I use pg_ugrade with kink option.

2) Did you run ANALYZE to collect statistics after the upgrade?

Yes. I ran vacuumdb-analyze in stages after the upgrade

3) Did you transfer the configuration, or did you just create a new
cluster with the default values?

I transfer the configuration

4) What exactly is slower? Queries? Inserts?

queries

5) Can you quantify the impact? Is it 2x slower? 100x slower?

it's more than 5 times slower than before. Very high load averages 

On Wed, Apr 17, 2024 at 1:25 PM Tomas Vondra <tomas.vondra@enterprisedb.com> wrote:

On 4/17/24 19:13, Johnathan Tiamoh wrote:
> Hello,
>
>
> I performed an  upgrade from postgresql-9.5 to postgresql-14 and the
> performance has degraded drastically.
>
> Please, is they any advice on getting performance back ?
>

There's very little practical advice we can provide based on this
report, because it's missing any useful details. There's a number of
things that might have caused this, but we'd have to speculate.

For example:

1) How did you upgrade? pg_dump or pg_upgrade?

2) Did you run ANALYZE to collect statistics after the upgrade?

3) Did you transfer the configuration, or did you just create a new
cluster with the default values?

4) What exactly is slower? Queries? Inserts?

5) Can you quantify the impact? Is it 2x slower? 100x slower?


regards


--
Tomas Vondra
EnterpriseDB: http://www.enterprisedb.com
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