Message-ID: <44027.216.41.12.254.1149608278.squirrel@webmail.webopticon.org>
In-Reply-To: <20060606152949.GB10018@phlogiston.dyndns.org>
References: <1149534308.3583.56.camel@bg002441.pro-unlimited.com>
	<22706.1149538039@sss.pgh.pa.us>
	<20060605203851.GB7071@phlogiston.dyndns.org>
	<23915.1149541591@sss.pgh.pa.us>
	<1149604741.2621.487.camel@localhost.localdomain>
	<17148.1149605005@sss.pgh.pa.us>
	<1149605576.2621.502.camel@localhost.localdomain>
	<17426.1149606369@sss.pgh.pa.us>
	<20060606152949.GB10018@phlogiston.dyndns.org>
Date: Tue, 6 Jun 2006 11:37:58 -0400 (EDT)
Subject: Re: Some queries starting to hang
From: "A.M." <agentm@themactionfaction.com>
To: pgsql-performance@postgresql.org
User-Agent: SquirrelMail/1.5.1 [CVS]
MIME-Version: 1.0
Content-Type: text/plain;charset=iso-8859-1
Content-Transfer-Encoding: 8bit

Hmmm...It could generate NOTICEs whenever there is a drastic difference in
rowcount or actual time...

On Tue, June 6, 2006 11:29 am, Andrew Sullivan wrote:
> On Tue, Jun 06, 2006 at 11:06:09AM -0400, Tom Lane wrote:
>
>>> it was properly instrumented. That way, the OP might have been able
>>> to discover the root cause himself...
>>
>> I don't think that helps, as it just replaces one uncertainty by
>> another: how far did the EXPLAIN really get towards completion of the
>> plan?  You still don't have any hard data.
>
> Well, you _might_ get something useful, if you're trying to work on a
> maladjusted production system, because you get to the part that trips the
> limit, and then you know, "Well, I gotta fix it that far, anyway."
>
> Often, when you're in real trouble, you can't or don't wait for the
> full plan to come back from EXPLAIN ANALYSE, because a manager is helpfully
> standing over your shoulder asking whether you're there yet.  Being able
> to say, "Aha, we have the first symptom," might be helpful to users.
> Because the impatient simply won't wait for the
> full report to come back, and therefore they'll end up flying blind
> instead.  (Note that "the impatient" is not always the person logged in
> and executing the commands.)
>
> A
>
>
> --
> Andrew Sullivan  | ajs@crankycanuck.ca
> I remember when computers were frustrating because they *did* exactly what
>  you told them to.  That actually seems sort of quaint now. --J.D. Baldwin
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Have you searched our list archives?
>
>
> http://archives.postgresql.org
>
>