Effective IO Concurrency
Hi!
In PostgreSQL 13, the way of using effective_io_concurrency has changed. Until v12, I used 200 for this value (using SSD drives). Using the new formula described in [ https://www.postgresql.org/docs/13/release-13.html | https://www.postgresql.org/docs/13/release-13.html ] gives me 1176. However, in the documentation [ https://www.postgresql.org/docs/13/runtime-config-resource.html#GUC-EFFECTIVE-IO-CONCURRENCY | https://www.postgresql.org/docs/13/runtime-config-resource.html#GUC-EFFECTIVE-IO-CONCURRENCY ] it says that the maximum value allowed is 1000.
On Mon, 2020-09-14 at 10:39 -0300, luis.roberto@siscobra.com.br wrote:
In PostgreSQL 13, the way of using effective_io_concurrency has changed. Until v12,
I used 200 for this value (using SSD drives). Using the new formula described in
https://www.postgresql.org/docs/13/release-13.html gives me 1176.
However, in the documentation https://www.postgresql.org/docs/13/runtime-config-resource.html#GUC-EFFECTIVE-IO-CONCURRENCY
it says that the maximum value allowed is 1000.
Then use the value 1000...
Yours,
Laurenz Albe
--
Cybertec | https://www.cybertec-postgresql.com
On 9/14/20 11:03 AM, Laurenz Albe wrote:
On Mon, 2020-09-14 at 10:39 -0300, luis.roberto@siscobra.com.br wrote:
In PostgreSQL 13, the way of using effective_io_concurrency has changed. Until v12,
I used 200 for this value (using SSD drives). Using the new formula described in
https://www.postgresql.org/docs/13/release-13.html gives me 1176.
However, in the documentation https://www.postgresql.org/docs/13/runtime-config-resource.html#GUC-EFFECTIVE-IO-CONCURRENCY
it says that the maximum value allowed is 1000.Then use the value 1000...
I think he means that the formula should take that into account.
--
Angular momentum makes the world go 'round.
De: "Ron" <ronljohnsonjr@gmail.com>
Para: "pgsql-general" <pgsql-general@lists.postgresql.org>
Enviadas: Segunda-feira, 14 de setembro de 2020 13:10:23
Assunto: Re: Effective IO Concurrency
On 9/14/20 11:03 AM, Laurenz Albe wrote:
On Mon, 2020-09-14 at 10:39 -0300, luis.roberto@siscobra.com.br wrote:
In PostgreSQL 13, the way of using effective_io_concurrency has changed. Until v12,
I used 200 for this value (using SSD drives). Using the new formula described in
https://www.postgresql.org/docs/13/release-13.html gives me 1176.
However, in the documentation https://www.postgresql.org/docs/13/runtime-config-resource.html#GUC-EFFECTIVE-IO-CONCURRENCY
it says that the maximum value allowed is 1000.Then use the value 1000...
I think he means that the formula should take that into account.
--
Angular momentum makes the world go 'round.
Exactly....
For future reference, and maybe a updated documentation:
SELECT least(round(sum(OLD / n::float)),1000) FROM generate_series(1, OLD) s(n)
I don't know how to write patches, so maybe someone can do that.
Thanks.