Re: Long running queries degrade performance - Mailing list pgsql-performance

From Mike Nolan
Subject Re: Long running queries degrade performance
Date
Msg-id 200404162025.i3GKPDe4013710@gw.tssi.com
Whole thread Raw
In response to Re: Long running queries degrade performance  (Chris Kratz <chris.kratz@vistashare.com>)
Responses Re: Long running queries degrade performance
List pgsql-performance
> Fairly sure, when it is happening, postgres usually is taking up the top slots
> for cpu usage as reported by top.  Perhaps there is a better way to monitor
> this?

Given the intermittent nature of the problem and its relative brevity
(5-10 seconds), I don't know whether top offers the granularity needed to
locate the bottleneck.

> likely you have a situation where something else is happening which blocks
> the current thread.

It happens on my development system, and I'm the only one on it.  I know
I've seen it on the production server, but I think it is a bit more
common on the development server, though that may be a case of which system
I spend the most time on.  (Also, the production server is 1300 miles away
with a DSL connection, so I may just be seeing network delays some of
the time there.)

> Both of these were triggered by users double clicking links in our
> web app and were fixed by a better implementation.  Perhaps something like
> that is causing what you are seeing.

My web app traps double-clicks in javascript and ignores all but the first one.
That's because some of the users have mice that give double-clicks even
when they only want one click.
--
Mike Nolan

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