Re: change on_exit_nicely_list array to the dynamic array to increase slots at run time for pg_restore

On Tue, 11 Mar 2025 at 11:58, Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> On Mon, Mar 10, 2025 at 2:24 PM Mahendra Singh Thalor
> <mahi6run@gmail.com> wrote:
> >
> > Hi,
> > (refer file src/bin/pg_dump/pg_backup_utils.c)
> >
> > While doing some code changes with pg_dumpall and pg_rsetore[1], we noticed that on_exit_nicely_list array has only
fixedslots (MAX_ON_EXIT_NICELY=20) but in some cases, we need more slots for pg_restore. 
> > Ex: restore more than 20 databases by single pg_restore command.
> >
> > We are working on a patch[1] which dumps all the databases in non-text mode by pg_dumpall and then we are restoring
thosedumps by pg_restore. So we need more slots due to multiple databases. 
> >
> > Apart from the attached patch solution, we thought of some more solutions.
> > Solution 1: reset array index with each database restore, but this might break some other things.
> > Solution 2: for each database, we can keep the index of the on_exit_nicely_list array and after restoring a
particulardatabase we can reset the index to old value but this looks like a hack. 
> >
> > Here, I am proposing a patch which will dynamically enlarge the on_exit_nicely_list array by doubling the previous
size.
> >
> > Thoughts?
>
> This reply might belong in another thread, but since you raised the
> issue here, instead of registering multiple functions with
> exit_nicely, why not modify the argument of the exit function
> (archive_close_connection()) to handle multiple arguments? In short,
> you could change ShutdownInformation[1] so that, instead of holding a
> single "Archive," it holds a list, allowing you to append different
> Archive handles to the list.
>
> [1]
> typedef struct ShutdownInformation
> {
>    ParallelState *pstate;
>    Archive *AHX;      -> change this to List of Archive*
> } ShutdownInformation;
>

Thanks Tom and Dilip for feedback.

As per above discussion, I did cleanup in different ways to fix the
problem in "non-text mde for pg_dumpall" patch.

--
Thanks and Regards
Mahendra Singh Thalor
EnterpriseDB: http://www.enterprisedb.com