Re: pg_upgrade 13.6 to 15.1?

On Sun, 15 Jan 2023 13:00:58 -0800 Adrian Klaver wrote:

>On 1/15/23 12:41, pf(at)pfortin(dot)com wrote:
>> On Sun, 15 Jan 2023 12:23:10 -0800 Adrian Klaver wrote:
>>
>>> On 1/15/23 11:27, pf(at)pfortin(dot)com wrote:
>>>> Hi,
>>>>
>>>> I'm fairly new to postgres; but have databases with about 2TB of data.
>>>>
>>>> Trying to upgrade from 13.6 to 15.1, pg_upgrade complains with:
>>>> [postgres(at)pf ~]$ /usr/bin/pg_upgrade -b /usr/local/pgsql/bin -B /usr/bin \
>>>> -d /mnt/db/var/lib/pgsql/data -D /mnt/work/var/lib/pgsql/data \
>>>> -s /tmp -U postgres
>>>
>>>> Nothing I read implies the need to upgrade to 14.x first... Right?
>>>
>>> In addition to Tom Lane's comments I would recommend reading this:
>>>
>>> https://www.postgresql.org/docs/current/pgupgrade.html
>>>
>>> multiple times. There is a lot going on there and it will take a couple
>>> of reads at least to begin to understand it all.
>>
>> Yup... that's what I've been working from... See my reply to Tom re
>> --link...
>
>1) Working from and understanding are two different things. For instance
>further on in the docs there is:
>
>--clone
>
> Use efficient file cloning (also known as “reflinks” on some
>systems) instead of copying files to the new cluster. This can result in
>near-instantaneous copying of the data files, giving the speed
>advantages of -k/--link while leaving the old cluster untouched.
>
> File cloning is only supported on some operating systems and file
>systems. If it is selected but not supported, the pg_upgrade run will
>error. At present, it is supported on Linux (kernel 4.5 or later) with
>Btrfs and XFS (on file systems created with reflink support), and on
^^^^^^^^^^^^^

Unless there's an update to pg_upgrade that's still undocumented; this is
not an option since like so many Linux users, my file system is ext4.

>macOS with APFS.
>
>2) From the docs:
>
>Run pg_upgrade
>
>Always run the pg_upgrade binary of the new server, not the old one.
>pg_upgrade requires the specification of the old and new cluster's data
>and executable (bin) directories. You can also specify user and port
>values, and whether you want the data files linked or cloned instead of
>the default copy behavior.
>
>
>3) Again, read the docs multiple times there is a lot to understand.

Agreed. But they could be a little clearer... :)

>> Thanks!
>>
>>>>
>>>> Thanks
>>>> Pierre
>>>>
>>>>
>>>>
>>>
>>
>>
>