Re: BUG #3790: pg_restore error canceling statement due to user request

Alvaro Herrera wrote:
> Bruce Momjian escribi??:
> > Magnus Hagander wrote:
> > > On Fri, Nov 30, 2007 at 10:13:53AM +0000, Gregory Stark wrote:
> > > >
> > > > "Mike C." <smith.not.western@gmail.com> writes:
> > > >
> > > > > I don't know if this is either a wording change, or a more serious bug, but
> > > > > when I do a pg_restore (from a 8.1.9 setup) to a fresh 8.3beta3 created
> > > > > database (createdb command only), I repeatedly see:
> > > > >
> > > > > ERROR:  canceling statement due to user request
> > > > > CONTEXT:  automatic analyze of table "dbs.public.entity_event"
> > > >
> > > > This is intentional, though perhaps the wording is confusing. What impression
> > > > does the wording give you? Does it make you think something has gone wrong?
> > >
> > > The fact that it says ERROR kind of hints that something has gone wrong,
> > > no? (so yes, I agree the wording isn't very good)
> >
> > What is causing this?  Statement_timeout?  I see different wording for
> > that behavior.  Is the postmaster getting a signal from somewhere on the
> > system?
>
> It's the new autovacuum cancel stuff.

Ah, OK.  Right now we have these two cancel messages:

        if (cancel_from_timeout)
            ereport(ERROR,
                    (errcode(ERRCODE_QUERY_CANCELED),
                     errmsg("canceling statement due to statement timeout")));
        else
            ereport(ERROR,
                    (errcode(ERRCODE_QUERY_CANCELED),
                     errmsg("canceling statement due to user request")));

While the first one is fine, the second one is used for Control-C and
the new autovacuum code to exit an activity when it is blocking someone
from getting a table lock.  Perhaps we just need to change the wording
to "canceling statement" and not specify the cause.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://postgres.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +