Windows 7 Optimization – Disable Services

Looking to virtualize Windows 7 and deliver it as a virtual desktop?  Good for you!  But what are you going to do to the operating system to optimize it?  Not sure?  How about disable some services.  That always saves resources.  There are so many, which ones make the most sense?

Let’s assume you are using XenDesktop and Provisioning services single image management. That means changes made during the user session are deleted upon reboot.  If we keep that in mind, we have a better idea of what services we can disable because their value is severely diminished if changes are not stored across reboots.  Additionally, there are some services we don’t need or want in our corporate environment and others we don’t think are important but our users definitely want. Continue reading Windows 7 Optimization – Disable Services


A Virtual Desktop Storm Approaches

Rush hour. Something we all can relate to. Way back in time when I used to go to an office daily, I hated rush hour.  If I left home at a certain time, it would take me 45 minutes just to get to the office. But if I left just 15 minutes earlier, that same 45 minute trip would only take 15 minutes.  You might be asking yourself what this anecdote has to do with virtual desktops. Well, it’s all about managing a storm. I managed the rush hour storm by changing the time I left for work in the morning.  With virtual desktops, we need do something similar. If you don’t, you will encounter the fifth mistake in my list of top 10 mistakes to avoid Continue reading A Virtual Desktop Storm Approaches

What I learned at BriForum 2010

For those of you who didn’t know, last week was BriForum and I was able to attend as a speaker and as an attendee.  I think it was a great event, and I believe it was the largest one ever, so congratulations to Brian, Gabe and the TechTarget team.

What did I learn last week?  I learned 10 things, which ironically fits nicely into this blog. Without wasting more of your time, here are the Top 10 Things I Learned At BriForum all for your enjoyment 🙂

10. Lou Malnati’s is great pizza and only 2 blocks from the hotel. Is there anything better than Chicago Deep Dish pizza? Continue reading What I learned at BriForum 2010

Protection From Anti-Virus

Protection from antivirus.  Are you wondering if you read that correctly?  Yes, it is correct.  Odd isn’t it?  Anti-virus is there to protect us, but we also need to be protected from antivirus. Antivirus solutions are critical, even in a virtual desktop environment. Many people believe that because a hosted VM-based virtual desktop image is created from a real-only image that they are immune from virus.  That is only partially true.  When you reboot, the virus goes away because the changes to the base image are destroyed (including the virus), but what about that time period between getting infected and the next reboot? Those few hours are dangerous. Continue reading Protection From Anti-Virus

Windows 7 Migration at BriForum

What would you say if I were to tell you that migrating to a virtual desktop was no different than if you were going to migrate to Windows 7?  I’m being serious.  Migrating a user to a virtual desktop has many similarities to migrating a user to Windows 7 on a traditional desktop.  With a Windows 7 migration, we are concerned with hardware, operating system, applications, personalization, and more.  With a virtual desktop migration, we are focused on hardware, operating system, applications, personalization and more. Same focus areas. Interesting

Of course there are some differences. For example, regardless of the path you are taking, most organizations will create their “Corporate Desktop Image”. At its core, the standard desktop image would have similar configurations like removing games, disabling Media Center, adding anti-virus software, etc. This would be done if Windows 7 were on a traditional desktop or on a virtual desktop.  But on the virtual desktop we will likely do more. Continue reading Windows 7 Migration at BriForum

Beware of Improper Resource Allocation

If you ask me what type of desktop I need, I’m going to say, 2+ cores with at least 4+ GB of RAM, 500+GB hard drive, etc. If you look at what I really need, you will see 1 core and maybe 2 GB of RAM. In fact, when I look at my resource consumption, I get close to 2 GB of RAM by the end of the day due to the number of applications I have running, memory leaks in some of my applications, and applications not freeing up memory when closed.

Like me, many users only consume a fraction of their total potential desktop computing power, which makes desktop virtualization extremely attractive. By sharing the resources between all users, the overall amount of required resources is reduced. However, there is a fine line between maximizing the number of users a single server can support and providing the user with a good virtual desktop computing experience.

Improperly allocating resources to the virtual desktops is the 7th most common mistake make. Continue reading Beware of Improper Resource Allocation

Delivering Desktop Images at the School

In a previous post, I discussed how many different desktop images the ABC school district required for their desktop virtualization design: five. Read the previous blog to find out why five were needed. With 18,000 virtual desktops, the challenge now becomes on how to design/scale the Provisioning services environment. And even still, what happens if one Provisioning services server fails. What happens to the virtual desktops that server was supporting?

With the ABC School District, it was originally decided to use 8 servers, each with 6 NICs. However, since the release of the reference design, we are instead allocating 13 servers with 6 NICs each with the goal of being able to reduce the number to 8. Why the increase? Risk mitigation. The ABC School District wants to make sure there is no bottleneck on the virtual desktop streaming side of the architecture. That in turn made us modify the design to increase the number of servers with the hopes that during implementation we can reduce the number and utilize the servers for other purposes.

Estimating Provisioning services capacity is fairly straight forward. One can assume you can achieve 500 virtual desktop streams per 1Gpbs NIC. With 6 NICs in the server (subtract one for fault tolerance), we estimated 2500 streams. However, the ABC School District is unsure if their infrastructure is able to support that level of traffic coming from a single server, thus we increased the number of Provisioning Services servers. We will revisit if all 13 are required once production ramps up.

Regardless of the number of servers, we still need to figure out what happens in the event of a failure. First, some goodies about Provisioning services:

  1. Provisioning Services includes its own high availability option
  2. A Provisioning services high-availability grouping is not limited to 10 servers as many believe.

In order for high availability to function, the same vDisks must be available from each server. We could use a shared storage solution, but the school district is trying to keep costs under control. Instead, we will simply use the local storage on each of the Provisioning services servers. The servers will be configured with 2 spindles in a RAID 1 configuration. Will this be enough IOPS (we all know how much we love to talk IOPS)?

  • First, the Provisioning services servers will utilize many more read operations in comparison to writes (remember we are simply reading blocks of the vDisk, thus the higher read operations)
  • Second, we will reduce the overall IOPS requirements for the Provisioning services server by utilizing system cache. Because we are using Windows Server 2008 (and more importantly 64bit), we can have a large system cache. This allows us to keep many more blocks of the vDisk in memory, thus reducing the need to go to disk for read requests.

That is only a portion of the Provisioning Services design. If you want to know more you can

  1. Get the white paper. It is in the XenDesktop Design Handbook in the reference architecture section
  2. Attend the upcoming TechTalk

Daniel – Lead Architect

My virtual desktop journey