Don’t be a bottleneck — Scaling VDI and the benefits of Flash

Scaling VDI deployments can be a messy business. I’ve worked with IT departments with angry users, productivity issuesMessyScales, and outages — all as a result of poor performance in systems that have been scaled past their ability to perform.  In nearly every case, these are smart teams, staffed with VDI experts, and yet they’re still struck with crippling scalability issues. What gives?

VDI bottlenecks have changed

Issues with scalability change as technology evolves.   Since the dawn of the modern age of VDI (we’re talking VMware Horizon View and Citrix XenDesktop here). the biggest challenge with large scale VDI has been RAM. Many VDI VMs running simultaneously on only a few hosts result in RAM contention and poor VDI performance. In severe cases, swapping to slow disk storage results. The compounded issues with low RAM and slow storage grind large-scale VDI to a halt. Luckily, companies like Cisco (with UCS) and others built mechanisms for adding large amounts of RAM, cheaply, to physical hosts The cost to provide RAM has dropped, amount of available RAM has increased, and this bottleneck is, for the most part, no longer an insurmountable limitation.

The next bottleneck: Slow Storage dont-be-a-bottleneck

Of course, nobody can remove ALL bottlenecks from a system. When you resolve the worst bottleneck, it simply exposes the next worst. In the case of VDI, the next bottle neck is usually slow shared storage. Large physical hosts (with lots of RAM and CPU) connected to slow spinning disk arrays across a low-bandwidth SAN quickly become the limiting factor in VDI scalability. Even the most powerful of spinning disk arrays fails to keep up with boot storms, VM recompose cycles, and performance VDI users. The biggest symptoms of slow storage are long wait times, slow boot times, and general desktop latency. Users hate these! Imagine waiting 10 minutes to boot your desktop then seconds or minutes after clicking on an icon for the application to load – not just frustrating, but also costly in terms of person-hours and productivity.

Things Get Easier with…  the Power of Flash!

With high performance, low-latency, high-bandwidth all-flash Pure Storage systems, the storage bottleneck to VDI scalability is removed. The problem of slow, unresponsive SAN storage is simply eliminated. With all-flash storage, boot storms and other surges in storage consumption rates over the course of a day or week are easily handled without performance degradation or other user impacts. And day-to-day common tasks (boot-up, application access, file saving, graphics-using) become faster and smoother, often providing a better experience than a physical desktop due to the extensive data center resources available to users. All that flash performance enables scalability to previously unheard of levels on a single infrastructure instance. In fact, the existing best practice of scaling a single instance to no more than 5000 desktops is, in my opinion, no longer necessary. The power of modern all-flash storage enables a much higher consolidation ratio, even with a conservative approach to desktop failure domains and high availability.

Not All Flash is Created Equal

But not every all-flash storage system is equal in the context of VDI. Consistent low-latency high performance is everything to VDI users – it defines their experience – but not every all-flash array can provide it. In particular, concerns with outages due to disruptive maintenance are an issue. Disruptive scaling is also of particular concern! Many existing all-flash systems require downtime to add either capacity or performance (simply unacceptable!) Not so with Pure Storage. Our systems maintain 100% performance under load, during failure conditions, and during upgrades. So you can add VMs with confidence to the limits of the system you have and know that adding more means a simple, non-disruptive capacity upgrade if you have to get more storage for those VMs.

To learn more about Pure Storage and Virtual Desktop Infrastructure, please visit the following:

Learning more about Virtualization and All-Flash Storage

Earlier this year VMware announced the release of Horizon 6, the new software suite that includes VMware View. Since that time I’ve been doing a number of webinars for VMware and Pure customers that explain Horizon View and the benefits that Pure provides in virtual server and virtual desktop environments.

Check out my webinar with Sachin Sharma of VMware discussing Horizon 6 on Pure

The immediate benefits of Pure Storage for VDI are clear and easy to understand: all-flash storage removes the biggest performance bottleneck in VDI systems. Users actually love VDI desktops when the experience is consistent and high-performing. Pure delivers the storage that makes great VDI possible.

Of course, there are now lots of vendors beyond Pure that promise great VDI performance. Some of them (definitely not all!) can actually deliver that performance today.

But speed isn’t all you need for VDI. You also need reliability, scalability, and a reasonable price point. To date, only Pure really delivers on all these features while providing the excellent experience that comes from all-flash arrays.

If you want to learn more, definitely visit Pure’s webinar page and sign up for one of my upcoming sessions.

Virtualization Field Day 3 — Pure Storage

Here at Pure Storage we have the privilege of hosting the Virtualization Field Day 3 team last week.  It was a great event, despite the vicious nerf battle that occurred, and the VFD3 guys were good enough to film and stream it.  Here’s the link to the videos which include a great discussion by Vaughn Stewart and an appearance by me as the demo guy.


Pure Storage and the people who work there

Those of you who follow me via social media or other means may have noticed that I’ve “gone orange”.


Yes, as of January 2014 I’ve joined Pure Storage to work on Virtualization and Cloud solutions. It’s an exciting role at an exciting company.  I’m looking forward to the ride!

Check out this video we filmed a few weeks ago.  In it Neil Vashharajani (@nvachhar) explains to me the magic of Pure Storage and flash.