Re: executeQuery and busy waiting

Garrick,

It would help if you posted a small program to replicate the problem.

Dave
On Fri, 2003-06-27 at 14:44, Garrick Dasbach wrote:
> I'm working on a project with Postgresql and I'm running into a strange
> problem.
>
> I have a Java Program running on the Database server that periodicly
> connects to the Database and runs a pl/pgsql function.  This function
> should run fairly fast, but could take several minutes based on the load
> of the server and amount of information it needs to process.
>
> Running the function from psql takes 40 seconds under no load and
> minimal data, but when I run the function from java using JDBC it takes
> 20-30 minutes.
>
> Checking top, this is a Linux system, I see that the java program takes
> up 99% of the CPU when it's running this function through executeQuery.
> Is executeQuery() doing a busy wait for the data from postgres?  It
> seems a bit absurd that the executeQuery method would hijack 99% of the
> CPU waiting for results and slowing everything else on the system down.
>
> The second problem I am noticing is that if I move the java program to
> another machine, to keep java from stealing all the CPU cycles, the
> function still takes 20-30 minutes to run through java, but only takes
> 40 seconds to run through psql.  What's the deal?
>
> Any help would be appreciated.
>
> Garrick Dasbach
>
> Software Developer
> MusicRebellion.com, Inc.
> Garrick@musicrebellion.com
>
>
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Dave Cramer <Dave@micro-automation.net>