Hi Daniel,

Without knowing for sure, I would think that setting the minimum heap size to 20G would take some time to allocate. What about just setting the maximum heap size, and let the JVM handle the minimum size, or start lower, like 2G.

Best regards,
Søren Berg Glasius
GR8Conf Europe organizing team

GR8Conf ApS
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From: Daniel Price <danprice303@gmail.com>
Reply: users@groovy.apache.org <users@groovy.apache.org>
Date: May 9, 2016 at 18:28:38
To: users@groovy.apache.org <users@groovy.apache.org>
Subject:  Groovy Running Slower With More Memory

Good Afternoon.  I've been running some Groovy 2.4.2 scripts on a Windows 7 64-bit PC with 16GB of RAM.  My scripts are memory intensive SQL Server DB manipulators, and I have modified startGroovy.bat to:

%JAVA_OPTS% -Xms8192M -Xmx8192M

I recently gained access to a new server running Windows Server 2012 that has 32GB RAM and lots of flash disk, so I thought giving Groovy more RAM might allow the scripts to run faster.  So I installed Groovy on the server and modified startGroovy.bat to:

%JAVA_OPTS% -Xms20480M -Xmx20480M

But the new server runs my scripts about twice as slow as my PC.  This is true even with the exact same RAM settings in startGroovy.bat.

I don't know if I should expect to see a large decrease in run time based on additional RAM, but an increase seems odd to me.

Could this be due to OS differences?