Re: Pg 16: will pg_dump & pg_restore be faster?

On Wed, May 31, 2023 at 02:05:10PM +1200, David Rowley wrote:
> On Wed, 31 May 2023 at 13:13, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> > There is no mention of concurrency being a requirement. Is it wrong? I
> > think there was a question of whether you had to add _multiple_ blocks
> > ot get a benefit, not if concurrency was needed. This email about the
> > release notes didn't mention the concurrent requirement:
>
> My understanding had been that concurrency was required, but I see the
> commit message for 00d1e02be mentions:
>
> > Even single threaded
> > COPY is measurably faster, primarily due to not dirtying pages while
> > extending, if supported by the operating system (see commit 4d330a61bb1).
>
> If that's the case then maybe the beta release notes could be edited
> slightly to reflect this. Maybe something like:
>
> "Relation extensions have been improved allowing faster bulk loading
> of data using COPY. These improvements are more significant when
> multiple processes are concurrently loading data into the same table."

The release notes don't normally get into details on the magnitude of
the improvement in various circumstances.

> The current text of "PostgreSQL 16 can also improve the performance of
> concurrent bulk loading of data using COPY up to 300%." does lead me
> to believe that nothing has been done to improve things when only a
> single backend is involved.

Yes, agreed.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

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