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Thu, 29 Dec 2005

The always useful if somewhat ad-cluttered Tom's Hardware publishes some benchmarks on Opteron and Xeon CPU performance running ESX Server. Unfortunately, they were not able to test dual-core Intel Xeons. Although AMD chips did well in power consumption, for overall performance, as is often the case, your mileage will definitely vary depending on your driving habits.

As you can see from the results, you really must test your applications on both AMD and Intel platforms in order to properly decide which is the faster alternative - the results can be surprising. Before we started testing, we suspected the floating point intensive Cplex application would be much faster on the AMD platform, but we were wrong. Although Intel's new dual core Xeon can't outperform the AMD Opteron under conventional server environments, it is likely to give AMD a solid beating in the virtualization space.

One interesting result was their positive performance effects of Hyper Threading:

Our tests show that Intel's Hyper Threading processors can provide a substantial performance boost, even if the number of active VMs exceeds the logical HT processor count. This is clearly due to the fact that with virtualization, there is a higher chance of producing two instructions to run on the integer and floating point units simultaneously, than is the case in a simple Windows environment. You can say that the NetBurst technology (which features Hyper Threading) could be called VMBurst and that it eases your virtualization overhead. An Intel quad CPU server with dual core CPUs and 16 HT units is likely to give a similar AMD Opteron quad CPU dual core server a run for the money, even at a Xeon clock speed of just 2.8 GHz. We are looking forward to pitting these setups against each other. ...

VMTN Forum thread on this article. I've tried to stay away from religious arguments ever since I used both vi and emacs, but if you're so inclined, the forums have some good discussion of where we are in the market today. Here are some threads from just this month: one, two, three, four. (And don't even get them started on blades vs non-blades...)

posted by jtroyer at: 16:39 | | | permanent link

Fri, 23 Dec 2005

With the increase in the number of available downloadable virtual machines, there is also an increased interest in reducing their size. Virtual machines are still, at the end of 2005, a bit large for convenient and widespread electronic distribution. Daemon_b gives us his recipe for Reducing the size of Windows XP VMs for portability.

VMs usually have the problem of being the same size as a bloated physical install, thus it makes the size a little unwieldy for distribution.

With a goal of having a VM as an application framework, the footprint should be as small as possible. So here is a step by step method for reducing the amount of space needed for a WinXP Pro VM. ...

This will reduce the VM size to half, if not more. The maximium reduction is 80%.

What techniques do you recommend for reducing the size of a virtual machine, either Windows or Linux?

posted by jtroyer at: 13:44 | | | permanent link

Wed, 21 Dec 2005

Adrian Cockcroft came back from the Computer Measurement Group conference with some thoughts on virtualization's effects on measuring CPU virtualization:

My observation is that utilization is useless as a metric and should be abandoned. It has been useless in virtualized disk subsystems for some time, and is now useless for CPU measurement as well. There used to be a clear relationship between response time and utilization, but systems are now so complex that those relationships no longer hold. Instead, you need to directly measure response time and relate it to throughput. Utilization is properly defined as busy time as a proportion of elapsed time. The replacement for utilization is headroom which is defined as the unused proportion of the maximum possible throughput. Dave Fisk calls this Capability Utilization.

posted by jtroyer at: 17:23 | | | permanent link

If there is one technology that took hold in the enterprise in 2005, it's virtualization. The software moved from test and development and into the data center faster than anyone imagined, including the experts. And while there are sure to be some bumps in the road in 2006 as the technology moves from awareness to adoption, you can bet most IT pros will be running virtualization in the data center before the end of next year.

From Matt Stansberry at SearchDataCenter.com.

posted by jtroyer at: 17:18 | | | permanent link

Tue, 20 Dec 2005

Tom Kyte is putting the new vSMP feature of Workstation 5.5 to good use. He says "VMware 5.5 rocks":

I have an 2 cpu Dell machine in the basement I use a lot -- my main desktop type machine (it is a 10lb notebook) has a hyperthreaded P4 in it so -- I was very interested in SMP support in vmware. Normally, vmware uses 100% of one cpu when it is doing something really intense. Now with this setup, I can get 100% ofboth cpu's going. Huge difference in performance. The main reason this is "good" -- Oracle algorithms change radically when cpu_count goes from 1 to more than 1 (but don't set it to more than 1 on a single cpu machine! It won't be "a good thing"). In order to do tests of how something might scale (based on latch usage and such), I always had to get to my larger machines. Now I can do some of that on the road easier (and demonstrate the differences too -- I could only report "what happened on another machine" instead of showing it).

Not only that -- but the 2 cpu VM's run faster on my machines so far than the 1 cpu VM's -- by a measurable difference (we are not talking fractions of a second here, it is so far significant). In order to test, I installed the same OS (red hat AS 4.0) twice using the same options -- only one time the SMP version built itself and the other time a single cpu version. Then I installed 10gr2 twice on both VM's. Other than one having 2 cpus and one having only 1 cpu -- they were configured identically. The database runs measurably faster doing cpu intensive operations on the 2 way VM.

posted by jtroyer at: 10:41 | | | permanent link

A few recent interesting articles for your virtual enjoyment:

Disabling the VMWare network adapters from Christopher Miller.

When you are not running a VMWare session, you may want to disable the VMware virtual network adapters. I have found that they can slow down network operations on the host. Anything doing a UDP broadcast that is sent over all adapters will take much longer to run if they broadcast over the VMWare adapters. The ListAvailableSQLServers function call in the SQLDMO library is one example that I came across that slowed down dramatically with the VMWare adapters running.

\m/ at m*g33k tells you how to run Workstation as a service on Windows 2003. This is for development and testing only; not only does running a production server inside Workstation violate your license, you really want the management and scalability of GSX Server or ESX Server for a professional-grade service offering.

The main problem is that it needs to run as a guest within another OS, mine is running under Win2003Std SP1. This means that you need to ensure you're logged on at all times to this machine otherwise the images are not mounted. So, when the frickin' Automatic Update issues a restart on your behalf, down goes your AD/Exchange/SQL blah blah blah.

After much searching on the VMWare kb and much googling, i've discovered how you can set the images as standard-ish Windows services thus leaving them running even when you log off.

If you get your images running as services, they will restart themselves if your test machine reboots. You can also log off of the test box and connect via RDP from your workstation -- thus freeing up some resources if you find your machine running slow.

Tarry Singh dives down onto the Oracle DBA side with the fifth part of his series on bulding Oracle clusters with VMware: RACing ahead with Oracle on VMware - Part V: The powerful SRVCTL Utility.

posted by jtroyer at: 10:29 | | | permanent link

Wed, 14 Dec 2005

Jim at vmwarez has found a cheap, workable thin client solution to enable enterprise desktop hosting with ESX Server:

We had a need for a computer for a new employee on short notice.... so we thought to ourselves, why don't we just deploy XP on a vm... and then put one of our old crappy PCs at the new guy's desk... he can boot up into XP and the RDP to the vm. So we did it. About a week later, we did it again for another new employee. Now we're doing it when it is time to replace old PCs around the office. The only time this doesn't make sense is when the end user needs physical devices or the ability to run VM Player or the like.

One of our biggest problems was that we did not have or know (and still don't) know of a source for cheap thin clients. Our old PCs were fine, but the thought of burning another XP license just to remote desktop really burned me... It is very difficult to find a thin client for less than $300 or $400... so what do you do? the old PC and a $170 xp license isn't that bad of a deal after all, right? Wrong! There's management with every PC that is deployed. That XP box should have antivirus software on it, right? It should be on the domain, right? It should not be used for anything but RDPing to the vm, right? Sheesh. What a pain. Why can't we find a cheap thin client?!?!?!

Right now Jim is trying 2x, and is happy with it so far. It's not free as in speech or as in beer, but they do give you a free taste for the first 10 clients.

Update: Lots of good suggestions from the comments, including Citrix, SunRay, Knoppix, Pilot Linux , and just using RDP or Windows Terminal Services. The best solution, as usual, depends on your particular needs. Luckily, thin client computing has a long history and a mature set of technologies.

posted by jtroyer at: 18:01 | | | permanent link

Tue, 13 Dec 2005

I keep up several ongoing searches of blogs and web pages, and I see plenty of job descriptions scroll by that ask for VMware experience. And as far as I could tell, the IT users I met at VMworld in October were very happy with their jobs using VMware. How is the demand for IT jobs with VMware experience in your neck of the woods?

From the retro green-on-black blog For all things tech...:

Currently as I write this, I know there is a BIG demand for IT staff that are experienced with Virtualization technologies. I know for a fact that VMware certified people are in high demand because of this increased demand. As the technology progresses and adoption at the enterprise level increases, so does the demand for qualified people to administer and implement these solutions.

VMware's certification and training usually get high marks from their participants. Here's a quick note from Dan Parsons' IT Obsession: (While you're there, you may find his mini-howto on 802.1q VLAN trunking with VMware ESX Server and a Cisco switch useful.)

Today was the last day of the "Virtual Infrastructure with ESX Server" course I was taking. It was a wonderful course and the instructor couldn't have been better. I guess I'm not accustomed to teachers knowing what they're teaching. Must have something to do with where I went to high school. Anyway, I learned a lot and I love ESX Server even more now. I must get my hands on a fibre channel switch and a VirtualCenter license.

And if you are interested in taking the VMware Certified Professional (VCP) Exam, I'd recommend checking out both Dominic Rivera's vmwareprofessional site and Mike Laverick's RTFM ExamCrams. (That you should be participating in the VMware Forums I hope goes without saying.)

posted by jtroyer at: 15:06 | | | permanent link

Following on to last Friday's post on Keychain PCs, Michal Halecky is also considering his portable personal environment options. He mentions VMware Player, U3, BlackDog, LaCie GlobeTrotter Portable Linux Desktop, and a future "ultra mobile PC" concept device from Intel similar to the OQO.

From the VMTN Player Discussion Forums, a good tip from Matt when storing your virtual machine on a removable flash drive:

One performance note I found when trying this is that portable hard drives tend to be a bit slower than typical desktop hard drives, and flash memory drives (even the best ones) tend to be a lot slower. And Windows by default disables write caching on removable drives (good for safety if you like yanking cables without doing "safely remove hardware", but bad for performance). The upshot is our optimization for fast suspends ends up doing badly on slow uncached drives, and your VM may run slower than it should. One workaround for this is to set "mainMem.useNamedFile=FALSE" in your .vmx file for any VMs you plan to use on portable/slow drives. Or, you can turn on write caching for that drive (but only if you know what this means, and then be very careful about telling Windows before unplugging the drive!).

posted by jtroyer at: 08:01 | | | permanent link

Fri, 09 Dec 2005

From "The Virtual Firewall" by Vassilis Prevelakis in the Dec 2005 issue of ;login: , the USENIX magazine (USENIX membership required, but you can also go straight to the author's website for an older presentation. One of the interesting ideas was to protect a laptop connected through a USB-attached wifi device; the USB device can be controlled by the virtual firewall guest and made invisible to the laptop host OS.

There is no doubt that nowadays a firewall on each computer is necessary; this is why Microsoft is bundling a firewall with its Windows XP platform. So the question is really, Why have a separate firewall on a virtual machine, rather than a firewall as part of the base OS? It is fair to say that keeping the firewall separate simplifies its administration, as its configuration and maintenance are completely separate from that of the rest of the OS. This allows the management of the firewall to be carried out without requiring the cooperation of the workstation user, which may be a considerable advantage in centrally managed environments. ...

Moreover, it also simplifies upgrades and security patches to the VF, since these cannot affect the host OS. For example, we have a Windows 2000 machine that would only boot in safe mode after installing the latest OS service pack. Such considerations may impede timely upgrades and hence open windows of vulnerability to the system. Finally, changes to the firewall configuration cannot be done via a user-friendly interface that may hide vital information from the administrator. Most important, configuring an application on the host will not result in an accidental change in the firewall policy.

The system described here has been in operation for about six months and has been "stress-tested" by linking the workstation to unprotected wireless net works, taking it to numerous conferences and trade shows. We plan to use the platform to acquire long-term attack data that will help us refine the security policy of the VF and create a wireless network forensic database.

posted by jtroyer at: 16:36 | | | permanent link

Thu, 08 Dec 2005

Jason Buffington of NSI Software gives a nice overview of the value of virtualization in your business continuity strategy. It's focused on data replication, which while not the entire story of business continuity, is one of the most important chapters.

Typically, discussions around server virtualization seem to focus on consolidation, easier management, and facilitation of older applications/operating systems on newer platforms. However, there are some interesting and, in fact, exciting business continuity solutions that are empowered through server virtualization. Specifically, by combining virtual machines with a data protection/replication technology (which is the heart of most business continuity approaches), one can:

• Provide more complete high availability. While replication/availability solutions can certainly protect almost any application by itself, flawlessly, there are limitations when considering .many to one. availability configurations, particularly when multiple competing applications are involved.
• Enable more cost-effective disaster recovery. While replication technologies can absolutely deliver data to a scaled back remote site, virtual machines can reduce the secondary infrastructure even more.
• Create autonomy within a redundant infrastructure. For large corporations that wish to keep one business units resources separate from another, as well as for regional hot site providers wanting to keep one client customer from another, virtual machines allow multiple customers to leverage shared hardware without sacrificing security.

There is a white paper on VMTN that has more information on using NSI Double-Take with ESX Server.

posted by jtroyer at: 18:24 | | | permanent link

Mike Levin is looking to be Linux-enabled any time, any place, and is looking at his PC-on-a-keychain options. He looks at VMware Player, FingerGear's Bio Computer-On-a-Stick, and the Black Dog Mobile Personal Server.

So in the end, there appear to be 3 PC-on-a-keychain approaches. Two of them involve virtualization, and one uses "projection". Of the two virtualized approaches, one needs the host OS to be running, requires a free install, and gobbles up generally twice the resources, but is highly mature. The other requires taking over the host PC before the installed OS ever has a chance to boot, but doesn't appear as mature, and perhaps requires a deeper understanding of Linux to be productive. The non-virtualized approach may be the most promising in the long-term, because it operates almost independently of the host PC, but appears to be the least mature of all, and runs on a PowerPC processor. I think I'll be choosing the first (VMWare) option, because I'll be controlling the PC environments I use it on, and doing the free VM player install won't be an issue. And RAM is cheap, so I'll install plenty if that becomes an issue. And the clincher is that I'll be able to clone off and share my work with others relatively easily.

posted by jtroyer at: 18:14 | | | permanent link

Wed, 07 Dec 2005

Mark Gibbs of Network World has been touching on virtualization lately in his "Gearhead" column.

His December 5 column is entitled "The insanely cool VMware Player," a title I can endorse wholeheartedly. He goes over the basics of VMware Player, so if you haven't downloaded it yet, do go give him a read. I do have a few clarifications on this column:

• Although you can't install Player if you already have Workstation installed, the new release of Workstation 5.5 comes with a version of Player included already. Right there in the main directory is vmplayer.exe, which is a fully-functional version of VMware Player. It's easy to create a virtual machine in Workstation and then see how it would look and work inside Player.

• Being able to open virtual machines created with the evaluation version of Workstation is a feature, not a "curious licensing loophole." The point of Player is proliferation -- "run, share, evaluate" -- and we want you to be able to run all virtual machines inside it, no matter how they are created. Workstation is worth purchasing for many reasons beyond the simple creation of virtual machines, including its clone and snapshot features.

• Both VMware Player and the Browser Appliance are currently in beta release, and you can expect general availability soon. The Browser Appliance will continue to be periodically refreshed along with OS and application updates.

In his November 28 column, he covers several books, including this one on virtualization:

Our next book is back to a topic that we discussed in Gearhead and in Backspin: virtualization. Virtualization: From the Desktop to the Enterprise by Chris Wolf and Erik M. Halter (Apress) covers a large chunk of the commercial virtual machine market, including Microsoft Virtual PC and Virtual Server and all of the VMware products.

The subtitle is accurate in that the book does span the territory from the desktop to the enterprise and details installation, configuration and management of virtualization products. As for the enterprise end, there are chapters on using virtual file systems, building failover and load-balanced clusters, and virtualizing storage.

What we particularly like about Virtualization is that it is detailed and contains lots of information that complements the documentation of the products.

posted by jtroyer at: 18:53 | | | permanent link

Fri, 02 Dec 2005

Links of interest this week:

What if I move my desktop inside a virtual machine? How much will this cost? What do I gain? What do I lose?

RACing ahead with Oracle on VMware - Part IV: Installing RAC Database with ASM Option

Pop open the hood and get your hands dirty inside your .vmx files: Supersizing Virtual SCSI Drives:

I've heard that it's possible to add more virtual SCSI disks to VMware Workstation 5.0 virtual machines by editing the VM's configuration file. For various classes that I teach, I like performing demonstrations of how to setup software RAID, but would like to assign more than seven virtual SCSI disks to a VM, which is the limitation through the GUI. Is this possible?

Increase the size of your VMWare disk drive [partition]

checklist for virtual machine setup

VMware vs Virtual PC. He likes VMware Workstation's performance, Ctl-Alt keyboard release shortcut, USB support, and conversion of Virtual PC images. He does like Virtual PC's keyboard shortcuts and focus-handling better.

Geert Baeke's blog postings on virtualization

posted by jtroyer at: 16:44 | | | permanent link