Обсуждение: Autovacuum vacuums not setting start time in pg_stat_activity

This is on a 8.2.3 database; vacuums started by autovacuum don't get
their query_start time set.

select * from pg_stat_activity where current_query like 'VACUUM%';
-[ RECORD 1 ]-+---------------------------------------------
datid         | 16384
datname       | emma2
procpid       | 8674
usesysid      | 10
usename       | postgres
current_query | VACUUM public.userdata_2409_messages_history
waiting       | f
query_start   |
backend_start | 2007-06-12 15:29:53.376641-05
client_addr   |
client_port   |

--
Jim Nasby                               jim.nasby@enterprisedb.com
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)

"Jim Nasby" <jim.nasby@enterprisedb.com> writes:
> This is on a 8.2.3 database; vacuums started by autovacuum don't get
> their query_start time set.

Hmm.  Query_start is actually defined as "time of last client command
receipt", so it's null just like client_addr/port are.  Not sure if
there's anything we should put there that's more meaningful than the
backend start time.

            regards, tom lane

Tom Lane wrote:
> "Jim Nasby" <jim.nasby@enterprisedb.com> writes:
> > This is on a 8.2.3 database; vacuums started by autovacuum don't get
> > their query_start time set.
>
> Hmm.  Query_start is actually defined as "time of last client command
> receipt", so it's null just like client_addr/port are.  Not sure if
> there's anything we should put there that's more meaningful than the
> backend start time.

Let's put the current command (vacuum/analyze) start time in there.
Backend start time, I assume, is the time at which the current autovac
iteration was started.

Should this be backpatched if changed in 8.3?

--
Alvaro Herrera                          Developer, http://www.PostgreSQL.org/
"El hombre nunca sabe de lo que es capaz hasta que lo intenta" (C. Dickens)

Alvaro Herrera <alvherre@commandprompt.com> writes:
> Should this be backpatched if changed in 8.3?

I'd vote no; it's pretty hard to argue that it's a bug fix
as opposed to a cosmetic improvement.

            regards, tom lane