From: maumau307 at gmail.com (MauMau)
Date: Mon, 14 Apr 2014 20:54:51 +0900
Subject: [Pljava-dev] Is it safe to use multi-threaded PL/Java in
	single-threaded postgres process?
In-Reply-To: <534BAE6D.9050201@tada.se>
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Message-ID: <D40AEDF3497A484BBCC1DEB79CD5CB3E@maumau>

From: "Thomas Hallgren" <thomas at tada.se>
> 3. For a test like yours, the time it takes to execute the actual 
> statement is important. The execution may be so slow that the overhead 
> imposed by the network call becomes negligible. A test using a lightweight 
> "SELECT 1" instead of the heavier "UPDATE testtable" would reveal such 
> issues.

Yeah, I thought this is the most likely.  We are trying to speed up batch 
jobs dramatically, and I hoped PL/Java's in-process architecture would 
contribute to that.

But I wonder why in-process execution didn't make a big difference.  I 
expected several times of difference because I saw the PollPosition 
benchmark results at http://hsqldb.org/.  It compares HSQLDB's in-process 
and client-server execution models.  I assume the client and the server ran 
on the same host.

Anyway, in-process and out-of-process execution doesn't seem to make a big 
difference for batch jobs which issue many SQL statements.

Regards
MauMau