Re: [PATCH v1] pg_ls_tmpdir to show directories

On Fri, Dec 27, 2019 at 06:50:24PM +0100, Fabien COELHO wrote:
> >On Fri, Dec 27, 2019 at 05:22:47PM +0100, Fabien COELHO wrote:
> >>The implementation simply extends an existing functions with a boolean to
> >>allow for sub-directories. However, the function does not seem to show
> >>subdir contents recursively. Should it be the case?
> >
> >>STM that "//"-comments are not project policy.
> >
> >Sure, but the patch is less important than the design, which needs to be
> >addressed first. The goal is to somehow show tmpfiles (or at least dirs) used
> >by parallel workers. I mentioned a few possible ways, of which this was the
> >simplest to implement. Showing files beneath the dir is probably good, but
> >need to decide how to present it. Should there be a column for the dir (null
> >if not a shared filesets)? Or some other presentation, like a boolean column
> >"is_shared_fileset".
>
> Why not simply showing the files underneath their directories?
>
> /path/to/tmp/file1
> /path/to/tmp/subdir1/file2
>
> In which case probably showing the directory itself is not useful,
> and the is_dir column could be dropped?

The names are expected to look like this:

$ sudo find /var/lib/pgsql/12/data/base/pgsql_tmp -ls
142977 4 drwxr-x--- 3 postgres postgres 4096 Dec 27 13:51 /var/lib/pgsql/12/data/base/pgsql_tmp
169868 4 drwxr-x--- 2 postgres postgres 4096 Dec 7 01:35 /var/lib/pgsql/12/data/base/pgsql_tmp/pgsql_tmp11025.0.sharedfileset
169347 5492 -rw-r----- 1 postgres postgres 5619712 Dec 7 01:35 /var/lib/pgsql/12/data/base/pgsql_tmp/pgsql_tmp11025.0.sharedfileset/0.0
169346 5380 -rw-r----- 1 postgres postgres 5505024 Dec 7 01:35 /var/lib/pgsql/12/data/base/pgsql_tmp/pgsql_tmp11025.0.sharedfileset/1.0

I think we'd have to show sudbdir/file1, subdir/file2, not just file1, file2.
It doesn't seem useful or nice to show a bunch of files called 0.0 or 1.0.
Actually the results should be unique, either on filename or (dir,file).

"ls" wouldn't list same name twice, unless you list multiple dirs, like:
|ls a/b c/d.

It's worth thinking if subdir should be a separate column.

I'm interested to hear back from others.

Justin