Feeds

The art of optimising VM performance

Physical and virtual hiccups

  • alert
  • submit to reddit

High performance access to file storage

Lab While it is unfair to say (as many vendors do), that server virtualisation will take over the world during the course of the next fifteen minutes, we know from the readers of The Register that ever-expanding numbers of virtual machines (VMs) are being spun up by organisations large and small.

A primary driver for early server virtualisation projects has been to consolidate footprint onto a smaller number of physical servers, each running multiple VMs. But are virtual systems making best use of the resources at their disposal?

You also told us that the routine management of virtualised systems can be problematic, to put it lightly. But considering the drive for server consolidation in particular, there has been nowhere near as much discussion around how to configure the physical resources allocated to VMs at run time. The same goes for sizing physical host servers in order to optimize service delivery while keeping control of costs.

So how does an administrator set about specifying the amount of RAM, disk space and I/O for each virtual machine? A good starting point is to monitor the physical resource consumption of the original servers hosting the applications over their typical work cycles. This information can then form the basis for working out just how much resources the corresponding VMs will consume, after adding in the requirements of the virtual server software itself.

So while some testing and experimentation can provide an idea of the needs of each individual VM the next question becomes one of working out which VMs to run on which physical servers. Getting this right can be tricky, especially in terms of working out how to satisfy the I/O requirements of the combined virtual servers and, more particularly, to ensure that all of the networking needs are adequately resourced.

Of course, real life is rarely so accommodating and we know that many of you report significant challenges in getting resource allocation right. There is a risk that virtual machines running on your systems have been allocated more physical resources than they actually require, especially if management tools cannot provide visibility into opportunities for optimising resource consumption.

If you have any examples of how to manage the physical resources allocated to each VM we would be very interested to hear what you do. Your comments in the past have indicated that VMs tend to be set up once and then left alone until something changes the status quo, thus leaving open the potential that physical resources may have been allocated but not used.

We also need to remember that today the majority of environments run their virtual servers in a relatively static mode. Virtualisation holds the promise of flexibility to cater for changing workloads and business demands, but so far few organisations have taken advantage of this capability. In order to do this properly, a way of dynamically allocating physical resources to virtual machines is required. We’d like to hear about how you’re making all this work, whether you’re doing it manually or if you’re one of those ‘dynamic’ types. ®

Combat fraud and increase customer satisfaction

More from The Register

next story
This time it's 'Personal': new Office 365 sub covers just two devices
Redmond also brings Office into Google's back yard
Inside the Hekaton: SQL Server 2014's database engine deconstructed
Nadella's database sqares the circle of cheap memory vs speed
Oh no, Joe: WinPhone users already griping over 8.1 mega-update
Hang on. Which bit of Developer Preview don't you understand?
Microsoft lobs pre-release Windows Phone 8.1 at devs who dare
App makers can load it before anyone else, but if they do they're stuck with it
Half of Twitter's 'active users' are SILENT STALKERS
Nearly 50% have NEVER tweeted a word
Internet-of-stuff startup dumps NoSQL for ... SQL?
NoSQL taste great at first but lacks proper nutrients, says startup cloud whiz
IRS boss on XP migration: 'Classic fix the airplane while you're flying it attempt'
Plus: Condoleezza Rice at Dropbox 'maybe she can find ... weapons of mass destruction'
OpenSSL Heartbleed: Bloody nose for open-source bleeding hearts
Bloke behind the cockup says not enough people are helping crucial crypto project
Ditch the sync, paddle in the Streem: Upstart offers syncless sharing
Upload, delete and carry on sharing afterwards?
prev story

Whitepapers

Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Five 3D headsets to be won!
We were so impressed by the Durovis Dive headset we’ve asked the company to give some away to Reg readers.
SANS - Survey on application security programs
In this whitepaper learn about the state of application security programs and practices of 488 surveyed respondents, and discover how mature and effective these programs are.