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On Thu, Nov 13, 2025 at 3:40=E2=80=AFAM CONVERS Yann - DREAL Auvergne-Rh=C3=B4ne-Alpes/CIDDAE/SIG wrote: > Hi, Processeurs is on of the parameters . An other is the outpout: input > capacity to write on disks. I purpose to test your hardware performance > with 12 jobs to begin and test less and high to learn which is better. Yo= u > can found it approximately > ZjQcmQRYFpfptBannerStart > This Message Is From an Untrusted Sender > You have not previously corresponded with this sender. > > ZjQcmQRYFpfptBannerEnd > > Hi, > > Processeurs is on of the parameters . An other is the outpout:input > capacity to write on disks. > > I purpose to test your hardware performance with 12 jobs to begin and tes= t > less and high to learn which is better. > > You can found it approximately with the rate of your speeding writing > ratio on disk or outpout of LAN card factoring by job's number. > > But testing IRL is more efficient. > > We use 7 jobs for =C3=A0 16 nprocs on saving on a master save dedicate to= with > car LAN 1000GhZ for example. > > We do it online but without clients traffic and without maintenance > operation. > > Tell us wich is your better choice! > > Bye > > Yann > > > Le 12/11/2025 =C3=A0 17:11, > ronljohnsonjr (par Internet, d=C3=A9p=C3=B4= t > pgsql-admin-owner+m63745-708218@lists.postgresql.org) a =C3=A9crit : > > On Wed, Nov 12, 2025 at 10:34=E2=80=AFAM Sam Stearns wrote: > >> Howdy, >> >> Would someone be able to advise on the correct setting for the -j option >> of pg_dump to run the dump in parallel, please? Is it based on CPU coun= t, >> or something else? The output of nproc is 32. >> > > I'd certainly never go *beyond* $(nproc), but since COPY generates a lot > of IO and compression burns through CPU, it all depends on the system's > other workload. Only you know what your system's other workload is when > pg_dump is running. > > -- > Death to , and butter sauce. > Don't boil me, I'm still alive. > lobster! > > --=20 Samuel Stearns Team Lead - Database c: 971 762 6879 | o: 971 762 6879 | DAT.com --00000000000041eb3606437b4f24 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Thanks, Yann!

On Thu, Nov 13, 2025 at= 3:40=E2=80=AFAM CONVERS Yann - DREAL Auvergne-Rh=C3=B4ne-Alpes/CIDDAE/SIG = <yann.conv= ers@developpement-durable.gouv.fr> wrote:
Hi, Processeurs is on of the parameters . An other is the outpout:=E2=80=8A= input capacity to write on disks. I purpose to test your hardware performan= ce with 12 jobs to begin and test less and high to learn which is better. Y= ou can found it approximately
ZjQcmQRYFpfptBannerStart
This Message Is From an Untrusted Sender
You have not previously corresponded with this sender.
=C2=A0
ZjQcmQRYFpfptBannerEnd
=20 =20 =20

Hi,

Processeurs is on of the parameters . An other is the outpout:input capacity to write on disks.

I purpose to test your hardware performance with 12 jobs to begin and test less and high to learn which is better.

You can found it approximately with the rate of your speeding writing ratio on disk or outpout of LAN card factoring by job's number.

But testing IRL is more efficient.

We use 7 jobs for =C3=A0 16 nprocs on saving on a master save dedica= te to with car LAN 1000GhZ for example.

We do it online but without clients traffic and without maintenance operation.

Tell us wich is your better choice!

Bye

Yann


Le 12/11/2025 =C3=A0 17:11, > ronljohnsonjr (par Internet, d=C3=A9p=C3=B4t pgsql-admin-owner+m63745-708218@lists.postgresql.org) a =C3=A9crit=C2=A0:
=20
Howdy,

Would someone be able to advise on the correct setting for the -j option of pg_dump to run the dump in parallel, please?=C2=A0 Is it based on CPU count, or something else?=C2=A0 The output of nproc is 32.

I'd certainly never go beyond=C2=A0$(nproc), but si= nce COPY generates a lot of IO and compression burns through CPU, it all depends on the system's other workload.=C2=A0 Only you= know what your system's other workload is when pg_dump is running.=

--
Death to <Redacted>, and butter sauce.
Don't boil me, I'm still alive.
<Redacted> lobster!


--

Samuel Stearns
Team Lead - Databas= e
c: 971 76= 2 6879 = | o: 97= 1 762 6879 | D= AT.com


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