Re: add timing information to pg_upgrade

On Fri, Jul 28, 2023 at 5:21 AM Nathan Bossart <nathandbossart@gmail.com> wrote:
>
> This information can be used to better understand where the time is going
> and to validate future improvements.  I'm open to suggestions on formatting
> the timing information, assuming folks are interested in this idea.
>
> Thoughts?

+1 for adding time taken.

Some comments on the patch:
1.
+    gettimeofday(&step_start, NULL);
+    gettimeofday(&step_end, NULL);
+    start_ms = (step_start.tv_sec * 1000L) + (step_start.tv_usec / 1000L);
+    end_ms = (step_end.tv_sec * 1000L) + (step_end.tv_usec / 1000L);
+    elapsed_ms = end_ms - start_ms;

How about using INSTR_TIME_SET_CURRENT, INSTR_TIME_SUBTRACT and
INSTR_TIME_GET_MILLISEC macros instead of gettimeofday and explicit
calculations?

2.
>   Checking database user is the install user                  ok (took 3 ms)
>   Checking database connection settings                       ok (took 4 ms)

+    report_status(PG_REPORT, "ok (took %ld ms)", elapsed_ms);

I think it's okay to just leave it with "ok  \t %ld ms", elapsed_ms);
without "took". FWIW, pg_regress does that way, see below:

ok 2         + boolean                                    50 ms
ok 3         + char                                       32 ms
ok 4         + name                                       33 ms


>   Performing Consistency Checks
>   -----------------------------
>   Checking cluster versions                                   ok (took 0 ms)
>   Checking database user is the install user                  ok (took 3 ms)
>   Checking database connection settings                       ok (took 4 ms)
>   Checking for prepared transactions                          ok (took 2 ms)
>   Checking for system-defined composite types in user tables  ok (took 82 ms)
>   Checking for reg* data types in user tables                 ok (took 55 ms)

Just curious, out of all the reported pg_upgrade prep_status()-es,
which ones are taking more time?

--
Bharath Rupireddy
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com