users@glassfish.java.net

Re: xen or openvz for Glassfish

From: Gabe Wong <gabrielw_at_ngasi.com>
Date: Fri, 29 Feb 2008 22:16:43 -0800

glassfish_at_javadesktop.org wrote:
> Hi *,
> I can't decide which virtualization is better (xen or openvz) for running Glassfish. I had hosting for both.
>
> XEN - 512RAM and 20GB
> Glassfish was installed started with - Xmx512m. Also mysql is running there.
>
> OPENVZ - 900RAM and 90GB
> Glassfish was started with -Xmx320m. When I tried to increase the size to -Xmx512m memory error is thrown.
>
> I want to use the hosting for web services, jms and CMS so I need large documents to be processed. For example to read the contents of pdf file.
>
> I have no knowlege about virtualization and I looks like the OPENVZ based hosting has to be a lot better then XEN but my problems with memory shows that it is not the same.
>
> PS: openvz is twice cheaper then xen.
> [Message sent by forum member 'valchev' (valchev)]
>
As the message indicates you do not have enough memory. For a full
fledge J2EE Application Server with a memory demanding application
you need at least 1GB Real RAM memory. Most Hosting providers include
SWAP in the calculation which is quite misleading.
You have to remember, in a VPS, memory is also needed for bootstrapping
the VPS as well as for other services, just as in a real system.

OpenVZ is cheaper as it shares resources with other applications and
VPS, while with Xen, CPU and RAM is allocated. Since it is Hypervisor
based, Xen, however should have better performance depending on the CPU
and memory allocation.

-- 
Regards
Gabe Wong
NGASI AppServer Manager
JAVA AUTOMATION and SaaS Enablement
http://www.ngasi.com
NEW! 8.0 - Centrally manage multiple physical servers