Re: CREATE DATABASE with filesystem cloning

Hi,

On Wed, 8 May 2024 at 16:58, Robert Haas <robertmhaas@gmail.com> wrote:
>
> On Tue, May 7, 2024 at 8:00 AM Nazir Bilal Yavuz <byavuz81@gmail.com> wrote:
> > We had an off-list talk with Thomas and we thought making this option
> > GUC instead of SQL command level could solve this problem.
> >
> > I am posting a new rebased version of the patch with some important changes:
> >
> > * 'createdb_file_copy_method' GUC is created. Possible values are
> > 'copy' and 'clone'. Copy is the default option. Clone option can be
> > chosen if the system supports it, otherwise it gives error at the
> > startup.
>
> This seems like a smart idea, because the type of file copying that we
> do during redo need not be the same as what was done when the
> operation was originally performed.
>
> I'm not so sure about the GUC name. On the one hand, it feels like
> createdb should be spelled out as create_database, but on the other
> hand, the GUC name is quite long already. Then again, why would we
> make this specific to CREATE DATABASE in the first place? Would we
> also want alter_tablespace_file_copy_method and
> basic_archive.file_copy_method?

I agree that it is already quite long, because of that I chose the
createdb as a prefix. I did not think that file cloning was planned to
be used in other places. If that is the case, does something like
'preferred_copy_method' work? Then, we would mention which places will
be affected with this GUC in the docs.

--
Regards,
Nazir Bilal Yavuz
Microsoft