From: Josh Berkus <josh@agliodbs.com>
Reply-To: josh@agliodbs.com
Organization: Aglio Database Solutions
To: daniel.haensse@swissembedded.com
Subject: Re: Transaction prioritization from java possible?
Date: Mon, 14 May 2007 10:22:03 -0700
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Daniel,

> basically we have  a transactional web application. The users can browse
> through some entries in the database and start a bunch of heavy queries
> that take up to 15 minutes (if multiple such heavy queries run in
> parallel the performance of the database and webinterface drops very
> quickly). The easiest thing will be to serialize these heavy queries and
> run it in the background. I can do this from the tomcat server.
> Now I would like to prioritize the webinterface user interaction over
> these heavy queries. How can I implement this from java?
>
> Ron mentioned this paper (see
> http://www.nabble.com/Background-vacuum-t3719682.html )
>
> And I finally found this:
> http://weblog.bignerdranch.com/?p=11
>
> Is there an easier way from java?

Check out the Bizgres project (www.bizgres.org).  They currently have a 
query-queuing system which will eventually be a contrib to mainstream 
PostgreSQL, but you should be able to use it for development right now.

-- 
--Josh

Josh Berkus
PostgreSQL @ Sun
San Francisco