Re: Database upgrade Pg11 to Pg12 issues

On Wed, Feb 3, 2021 at 10:07:03PM -0500, Craig McIlwee wrote:
>
> (replying to the entire list instead of Bruce only this time...)
>
>
>
> This doesn't make sense to me.  Since we hard-linked, why would 12 be so
> much smaller?  If it was symlinks, I could imaging that, but it doesn't
> use symlinks, just hard links, so it should be similar.  Please look at
> the size of main/base on both, since that is where your data is.  Maybe
> 11 just has a lot of old WAL that isn't copied.
>
>
>
> It depends on how the directory sizes were measured. "du" won't count the same
> file more than once, so if space was measured using one of the following
> commands:
>
> du -hs /var/lib/postgresql/
> du -hs /var/lib/postgresql/11/main /var/lib/postgresql/12/main 
>
> Then you would see a large value for the 11 directory and then the 12 directory
> would only show the files that weren't already counted when measuring the 11
> directory.  Running du on each version's directory separately might give
> results that are more in line with expectations.

Yes, I was assuming the du commands were run separately on each
directory.

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

The usefulness of a cup is in its emptiness, Bruce Lee