On telnet prompt

type

cat  /proc/user_beancounters

you will see something like this

uid  resource           held    maxheld    barrier      limit    failcnt
101: kmemsize       10069594   10087306   33554432   36909875          0
lockedpages           0          0       8192       9011          0
privvmpages      151948     151955     262144     262144        484
shmpages           3407       3407      32768      32768          0
dummy                 0          0          0          0          0
numproc             186        186        768        768          0
physpages         75888      75892          0 2147483647          0
vmguarpages 0          0     131072 2147483647          0
oomguarpages      79627      79631     266240 2147483647          0
numtcpsock           67         67       1080       1080          0
numflock             11         11        564        618          0
numpty                1          1         48         48          0
numsiginfo            0          1        768        768          0
tcpsndbuf        500636     500636    5160960    8110080          0
tcprcvbuf        602016     602016    5160960    8110080          0
othersockbuf      27736      27736    3378240    6291456          0
dgramrcvbuf           0       1400     786432     786432          0
numothersock         32         32       1080       1080          0
dcachesize            0          0   10727424   10874880          0
numfile            5873       5882      27936      27936          0
dummy                 0          0          0          0          0
dummy                 0          0          0          0          0
dummy                 0          0          0          0          0
numiptent            43         43        384        384          0

Check vmguarpages.

Memory guaranteed = vmguarpages *4 /1024

for eg if  vmguarpages =131072

memory = 131072 *4 /1024 = 512MB

This is your guaranteed RAM.

vmguarpages barrier =  number of 4K memory pages that your applications will always be able to allocate.

privvmpages =  that much of 4K memory pages your application are able to allocate but a request might not be granted. Consider vmguarpages as a memory guarantee, and privvmpages as a upper burstable limit.

If you need a script that will monitor your memory limits and also check for errors on your openVZ , check here

Last week In Oracle world, Oracle has unvielded Exalogic  Oracle Unveils Exalogic Elastic Cloud , which apart from tons of feature which you can read on Oracle’s blog ,comprises the latest high performance x86 hardware, the industry-leading Oracle WebLogic Server, and Exalogic software, all engineered by Oracle for maximum capability with minimum set-up.

Java will be the money-maker for cloud computing over the next few years. There’s a reason VMware focuses on Java, that Google App Engine added Java, and that Oracle now emphasizes Java performance. Enterprises pay big bucks for Java speed, and those moving to cloud architectures want as much Java performance as they can get.

Google also have moved to integrate java applications to the its cloud offering as it was not seeing much traction.

Yes there might be better alternatives coming up but Java is here to stay for long.

The user has compared the costs and performance of Linode, Slicehost, Prgmr, Rackspace and Amazon.

You can find the results here

Presentation Overview:

In this session users will take a deep dive at few cloud computing examples and participants will be able to know how to use cloud computing for Google App Engine and Amazon EC2.

The Google App Engine is a platform for developing and hosting web applications in Google-managed data centers. The Google App Engine is an example of cloud computing technology as it virtualizes applications across multiple servers and data centers. It is, at its heart, a powerful cloud computing platform designed to help you more easily create and manage scalable, JVM-based web applications. If you’re developing a Java application on App Engine you probably already know that you can use JPA and JDO Java persistence APIs to interact with the data store. Now learn how to take full advantage of these powerful APIs. We will explore few examples from Amazon EC2 like how to deploy groovy on grails application. We will also look at development tools to make your life easier while working with Amazon EC2, Amazon S3 and Simple db.

Presentation Overview

The ESB concept emerges from integration requirements that have remained mostly stable and pervasive over the years. Yet many developers feel like they are run over by the bus, especially when an ESB is foisted onto their projects. Open source ESBs offer a flexibility and transparency that is hard to match without access to the source code. In the first half of this talk, we will detail the architectural considerations behind ESBs and how they are realized in JBoss ESB. With this understanding, the audience should be well prepared to use and customize ESBs to meet their specific project needs.

To start with we had some issues on our linux hosted webserver and had to do some sanity checks by duping it, on somewhat a similar kernel. The usual system resource crunch and the nagging system admins put me on a no mans land.

Left with no options, I decided to do some checks using ubuntu kernel. Remember I still have my notebook (windows XP) to try stuff on, I could have easily partitioned and installed ubuntu with windows and done my job. But probably I was more inclined to virtualization and thought of trying it out. I did some groundwork and came up with options like Sun Microsystems Virtual Box, VMware, virtual pc etc to name a few.

Suns Virtual box is a x86 and AMD64/Intel64 virtualization product and that helps me so I decided to move ahead with it.You can get more details from the virtual box website

Now I was ready for the download, the download was pretty straight forward and the product picked up all the notebook attached devices.Now I had to create a virtual hard disc on my parent OS and the steps were easy and well documented. But be sure to know the memory& HD size,space specifications for the OS you would need to install (I gave a 8 GB size for my ubuntu virtual partition).The virtual machine was created on click of the finish button, it was that simple.

I got a latest version of ubuntu and cut a CD for it, started the virtual box program ..selected the mounted CD disc drive and now it was like a clean machine which is ready to take any brutality . I kick started the ubuntu installation likewise I would do in any normal installation and went for some coffee, by the time I was back the installation was compelete and I was running an OS on a virtual machine !!!

The keyboard was a bit nasty initially to control the virtual OS, but setting some special key combinations solved the issue. I did my sanity checks which was the whole purpose of the karma and it turned out to be a good karma and was able to solve the problem.

Also later I came to know of the tool Disk2vhd by microsoft which is a utility for creating VHD (Virtual Hard Disk) which can be imported as an image/snapshot on our virtual box program. So in case you need to image your existing windows PC on another machine you can create a virtual hard disc out of it and import it. Making it possible to run the image as a virtual machine. Again the steps again are simple and its just clicks away.

Now am able to break the barriers of one OS/ machine and am able to test across platforms. Thanks to virtualization !! and hope this is of much help!

Top 5 Reasons to Adopt Virtualization Software

1.Get more out of your existing resources: Pool common infrastructure resources and break the legacy “one application to one server” model with server consolidation.

2.Reduce datacenter costs by reducing your physical infrastructure and improving your server to admin ratio: Fewer servers and related IT hardware means reduced real estate and reduced power and cooling requirements. Better management tools let you improve your server to admin ratio so personnel requirements are reduced as well.

3.Increase availability of hardware and applications for improved business continuity: Securely backup and migrate entire virtual environments with no interruption in service. Eliminate planned downtime and recover immediately from unplanned issues.

4.Gain operational flexibility: Respond to market changes with dynamic resource management, faster server provisioning and improved desktop and application deployment.

5.Improve desktop manageability and security: Deploy, manage and monitor secure desktop environments that users can access locally or remotely, with or without a network connection, on almost any standard desktop, laptop or tablet PC.

Here is an example how to Virtualize windows XP

Andi Mann, vice president of research at Enterprise Management Associates commented

SpringSource’s Enterprise Java Cloud is a service that is based on far more than merely acquiring Cloud Foundry.Certainly the functionality provided by Cloud Foundry is key, but SpringSource’s solutions for building, running and managing Java applications are ideally suited for applications that are deployed in the cloud. The new service brings this all together. For companies where the cloud deployment option makes sense, SpringSource has a killer offering.

Full news here

Today they lauched Enterprise Java cloud . From their blog post SpringSource Launches the Enterprise Java Cloud. The SpringSource Cloud Foundry Enterprise Java Cloud service is available immediately at CloudFoundry.com in beta and is free to use. Normal cloud service provider fees still apply

Understanding Cloud Computing

I came today at one of the blog post which explains to setup and get your first app running.
Here is the link.

This should prove helpful to the users who want to experiment with cloud computing.