Re: [Proposal] Adding callback support for custom statistics kinds

> On Dec 9, 2025, at 12:45, Michael Paquier <michael(at)paquier(dot)xyz> wrote:
>
> It seems to me that you are missing nothing here, and that Chao has
> missed the fact that the end of pgstat_read_statsfile() does a "goto
> done", meaning that we would take a round of

No, I didn’t miss that part. But in the “done” clause:

```
done:
/* First, cleanup the main stats file, PGSTAT_STAT_PERMANENT_FILENAME */
FreeFile(fpin);

elog(DEBUG2, "removing permanent stats file \"%s\"", statfile);
unlink(statfile);

/* Let each stats kind run its cleanup callback, if it provides one */
for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++)
{
const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind);

if (kind_info && kind_info->end_extra_stats)
kind_info->end_extra_stats(STATS_READ);
}
```

end_extra_stats(STATS_READ) has no failure indication.

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/