Re: GNU/Hurd portability patches

On Mon, Sep 22, 2025 at 07:02:25AM +0900, Michael Paquier wrote:
> On Sun, Sep 21, 2025 at 09:00:00AM +0300, Alexander Lakhin wrote:
> > So it seems to me that Hurd is not mature enough yet to test Postgres.
>
> I'd say that it is likely not mature enough for production. In terms
> of testing, that seems kind of OK.

Ack.

> However, failures like the one you are reporting here bring noise in
> the buildfarm, meaning that we would perhaps tend to ignore reports
> that are in fact legit because we don't really know what would be
> Hurd-related or Postgres-related.

I will keep an eye on it.

There have been two (infrequent) failures in the isoloation tests as
well, which I haven't had time to investigate further:

In PG15:

|test multiple-row-versions ... FAILED (test process exited with exit code 1) 145260 ms

This one is a segfault, it happened twice so far and only on REL_15_STABLE:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=fruitcrow&dt=2025-09-18%2007%3A57%3A40
https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=fruitcrow&dt=2025-09-03%2007%3A36%3A45

|setup failed: server closed the connection unexpectedly
| This probably means the server terminated abnormally
| before or while processing the request.

|/hurd/crash: [...]/buildroot/REL_15_STABLE/inst/bin/postgres -D data-C(25142) crashed, signal {no:11, code:2, error:2}, exception {1, code:2, subcode:0}, PCs: {
| 0x1019b4d34 0x1028ee2a0 0x10249e1ac 0x1025da71f 0x102596611 0x10049fe63,
| 0x102497aec 0x1028e674e 0x1024ada52 0x1024aeb2a 0x1024a785b 0x10291f5b7 0x10291f
| 625 0x1024c7242 0x1024986a2 0x1024c72c0,
| 0x102497aec 0x102572ace
| }, killing task

In PG17:

|not ok 98 - stats 2100 ms

|diff -U3 buildroot/REL_17_STABLE/pgsql.build/src/test/isolation/expected/stats_1.out buildroot/REL_17_STABLE/pgsql.build/src/test/isolation/output_iso/results/stats.out
|--- buildroot/REL_17_STABLE/pgsql.build/src/test/isolation/expected/stats_1.out 2025-09-15 22:06:24.000000000 +0100
|+++ buildroot/REL_17_STABLE/pgsql.build/src/test/isolation/output_iso/results/stats.out 2025-09-15 22:23:05.000000000 +0100
|@@ -1445,7 +1445,7 @@
|
| name |pg_stat_get_function_calls|total_above_zero|self_above_zero
| --------------+--------------------------+----------------+---------------
|-test_stat_func| 1|t |t
|+test_stat_func| 1|f |f
| (1 row)

This one happened twice as well, and so far only on REL_17_STABLE:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=fruitcrow&dt=2025-09-15%2021%3A06%3A17
https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=fruitcrow&dt=2025-09-13%2008%3A04%3A05

This might be due to the HPET timer not always being monotonic - there
has been an independent report via the Debian autobuilder and a GNU Mach
fix was committed last night, I'll check whether this can be
reproduced/confirmed-fixed with this change:

https://lists.gnu.org/archive/html/bug-hurd/2025-09/msg00020.html
https://salsa.debian.org/hurd-team/gnumach/-/commit/06079a8d212817ee0365f318bd90b67bf56bfb06

Michael