20.5.1
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/16/runtime-config-wal.html
Description:
The sentence in commit_siblings "A larger value makes it more probable that
at least one other transaction will become ready to commit during the delay
interval." seems to belong in commit_delay instead.
On Wednesday, February 7, 2024, PG Doc comments form <noreply@postgresql.org>
wrote:
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/16/runtime-config-wal.html
Description:The sentence in commit_siblings "A larger value makes it more probable that
at least one other transaction will become ready to commit during the delay
interval." seems to belong in commit_delay instead.
That sentence in that location is correct. See “birthday paradox”.
Maybe phrasing it in the negative will make things clear - the more
required sessions needed before allowing a delay the less likely the delay
will be wasted.
David J.
On Wed, 2024-02-07 at 09:59 -0700, David G. Johnston wrote:
On Wednesday, February 7, 2024, PG Doc comments form <noreply@postgresql.org> wrote:
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/16/runtime-config-wal.html
Description:The sentence in commit_siblings "A larger value makes it more probable that
at least one other transaction will become ready to commit during the delay
interval." seems to belong in commit_delay instead.That sentence in that location is correct. See “birthday paradox”.
To be more precise: if 15 other transactions are currently running, there
is a bigger chance that at least one of them will want to flush WAL before
"commit_delay" has expired than if there are only 3 other transactions.
Yours,
Laurenz Albe