Re: Intermittent stats test failures on buildfarm

Also, kookaburra (AIX) has a problem with the stats test as well.

What is most puzzling to me is that it only happens with cc (not gcc).
And I can only get it to happen when running a cronjob for the
buildfarm.  If I run it interactively, the stats collector will run
fine, or if I run the build script from the command line.

The environment between cron and from command line are not significantly
different, so I am at a bit of loss as to the reason why.

Any thoughts?
-rocco

> -----Original Message-----
> From: pgsql-hackers-owner@postgresql.org
> [mailto:pgsql-hackers-owner@postgresql.org] On Behalf Of Tom Lane
> Sent: Tuesday, August 30, 2005 12:31 AM
> To: pgsql-hackers@postgreSQL.org
> Subject: [HACKERS] Intermittent stats test failures on buildfarm
>
>
> I just spent a tedious hour digging through the buildfarm results
> to see what I could learn about the intermittent failures we're seeing
> in the stats regression test, such as here:
> http://www.pgbuildfarm.org/cgi-bin/show_log.pl?nm=ferret&dt=20
> 05-05-29%2018:25:09
> This is seen in both Check and InstallCheck steps.  A variant
> pathology
> is seen here:
> http://www.pgbuildfarm.org/cgi-bin/show_log.pl?nm=gerbil&dt=20
> 05-07-22%2007:58:01
> Notice that only the heap stats columns are wrong in this
> case, not the
> index stats.  I think that this variant behavior may have
> been fixed by
> this patch:
>
> 2005-07-23 20:33  tgl
>
>     * src/backend/postmaster/pgstat.c: Fix some failures to
> initialize
>     table entries induced by recent autovacuum integration.
>  Not clear
>     this explains recent stats problems, but it's definitely wrong.
>
> but it's not certain since nobody traced through the code to exhibit
> why those uninitialized table entries would have led to this
> particular
> visible symptom.  But with no occurrences of that behavior since the
> patch went in, I suspect it's fixed.
>
> What we are left with turns out to be multiple occurrences of
> the first
> pathology on exactly three buildfarm members:
>
>     ferret        Cygwin
>     kudu        Solaris 9, x86
>     dragonfly    Solaris 9, x86
>
> There are no occurrences of the failure on the native-Windows
> machines,
> nor on buzzard (Solaris 10, SPARC), nor on gerbil (Solaris 9, SPARC)
> (though gerbil has one old occurrence of the second
> pathology, so maybe
> that observation should be taken with a grain of salt).  And none
> whatever on any other buildfarm member.
>
> The same three machines are showing the failure in the 8.0
> branch, too,
> so it's not a recently-introduced issue.
>
> And one thing more: kudu and dragonfly are actually the same machine,
> same OS, different compilers.
>
> So what to make of this?  Dunno, but it is clearly a very
> platform-specific behavior.  Anyone see a connection between Cygwin
> and Solaris?
>
>             regards, tom lane
>
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