Combining apps in a virtual environment

Virtual matchmaking

Managers have to be cognizant of the personalities in play on their work teams. They aim for a mix of complementary characters to maximize team depth and minimize friction and conflict. When building a virtualized server environment, network architects and administrators face the same challenge teaming up applications on a single server.

"It's almost like you've got a horoscope chart, where different Zodiac signs like to go together," says Andrew Hillier, co-founder and CTO of data center analytics company Cirba.

The company has been in the data center analysis business since 1999. Now, the 55-person staff -- about half of them engineers -- focuses on virtualization. The company launched Version 4.4. of its Data Center Intelligence software, with increased integration with VMware's Virtual Infrastructure. The November release of 4.5 was full Unicode, responding to international demand.

DCI brings together configuration information, business attributes and utilization data of servers, representing them as a three-dimensional cube and finding opportunities to optimize their use through virtualization or consolidation. That's more than a question of slapping applications together on a physical server.

"They all have different affinities for each other, they all normalize differently to each other," Hillier says. Hence, the need to know your workload personalities -- the traits processes have.

The four big factors

"The whole trick about virtualization is to efficiently utilize the various resources," says Scott Elliott, senior systems network specialist with Christie Digital Systems Inc. and leader of the Southwest Ontario VMware User Group. There are four main categories to consider -- CPU, memory and network and disk I/O.

"At a very generic level, you have to watch out for those four big boys," Elliott says.

"If you have a footprint that's very high in one or more of those areas, putting another application that has a similar type of footprint could cause contention if you don't map out or provision out your hardware correctly," Elliott says.

Hillier says there are a finite number of archetypes or personalities. Data warehousing, for example, is largely read activity throughout the day, with bursts of write activity and moderate CPU strain. An online transaction processing (OLTP) app, on the other hand, has balanced read and write, with network activity mirroring the I/O.

The upside of similarity

But there's also a school of thought that says familiarity doesn't breed contempt: Similar virtual machines can make more efficient use of some resources, says Burton Group analyst Chris Wolfe.

"One of the issues that comes into play is sometimes you have separation of security zones on physical systems," Wolfe says. "Security separation may trump any type of performance load-balancing issues that you're trying to achieve."

There is an upside to running similar VMs. "It's not just necessarily trying to make sure you don't have any overlapping performance spikes when you consolidate, but the other benefit that you really get from like applications in the planning analysis is consistency of a memory footprint," Wolfe says. "You might actually wind up being able to run more VMs on a given physical host due to a consistency either with the applications or the host operating system. There would be a high degree of redundancy in the read-only memory pages the applications would need as well as their like operating systems."

Memory mapping does give an efficiency advantage, says Elliott. "If they're consistently accessing a spot in memory that is the same thing ... if you have two Windows applications and they're always hitting the same DLL again and again and again, you can get some memory savings if that DLL's just loaded once and you just have pointers to it," he says.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Dave Webb

Network World Canada
Show Comments

Cool Tech

Bang and Olufsen Beosound Stage - Dolby Atmos Soundbar

Learn more >

Toys for Boys

ASUS ROG, ACRONYM partner for Special Edition Zephyrus G14

Learn more >

Nakamichi Delta 100 3-Way Hi Fi Speaker System

Learn more >

Sony WF-1000XM3 Wireless Noise Cancelling Headphones

Learn more >

Family Friendly

Mario Kart Live: Home Circuit for Nintendo Switch

Learn more >

Philips Sonicare Diamond Clean 9000 Toothbrush

Learn more >

Stocking Stuffer

Teac 7 inch Swivel Screen Portable DVD Player

Learn more >

SunnyBunny Snowflakes 20 LED Solar Powered Fairy String

Learn more >

Christmas Gift Guide

Click for more ›

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Tom Pope

Dynabook Portégé X30L-G

Ultimately this laptop has achieved everything I would hope for in a laptop for work, while fitting that into a form factor and weight that is remarkable.

Tom Sellers

MSI P65

This smart laptop was enjoyable to use and great to work on – creating content was super simple.

Lolita Wang

MSI GT76

It really doesn’t get more “gaming laptop” than this.

Jack Jeffries

MSI GS75

As the Maserati or BMW of laptops, it would fit perfectly in the hands of a professional needing firepower under the hood, sophistication and class on the surface, and gaming prowess (sports mode if you will) in between.

Taylor Carr

MSI PS63

The MSI PS63 is an amazing laptop and I would definitely consider buying one in the future.

Christopher Low

Brother RJ-4230B

This small mobile printer is exactly what I need for invoicing and other jobs such as sending fellow tradesman details or step-by-step instructions that I can easily print off from my phone or the Web.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?