Citrix and VMware - Battling it out for Server, Desktop and App Virtualization Dominance

Citrix has long been an innovator in the App Virtualization space with its Metaframe/Presentation Server/XenApp product suite and is now extending its dominance to the Desktop Virtualization market with
XenDesktop.

Meanwhile the Server Virtualization space has been the fortress of VMware with VI3 and the new vSphere breaking all barriers to Server Virtualization.

While these two companies are dominating their own space in Virtualization, they are also actively trying to break into each other's strongholds by building their own products and fighting it out mostly on price point and simplicity.

Virtualize 100% of all DataCenter Workloads using vSphere:
IO Performance has traditionally been a weak spot for Virtualization products. This has hindered the
adoption of Virtualization for high IO intensive workloads like Databases. But with vSphere, VMware has drastically improved the IO performance reaching "just above 350,000 I/O operations per second". This should be good enough for even most IO intensive workloads.

One other good example of VMware's commitment towards 100% Virtualization is the addition of the new Virtual Hardware - SAS Drives. From the VMware docs:

Serial Attached SCSI (SAS) virtual device for Microsoft Cluster Service — Provides support for running Windows Server 2008 in a Microsoft Cluster Service configuration

You can see that VMware took all the extra effort to add this new virtual device just to ensure that MS Cluster Service in 2008 is a suitable candidate for Virtualization.

Citrix focuses on Virtualized Delivery of 100% of all Applications:
With the new releases of XenApp, Citrix can virtualize and deliver all the desktop applications available. With the new VM hosted App capability, Citrix has ensured the abaility to virtualize apps built for Desktop OSes like XP and Vista and that are not compatible with 2003 and 2008.

Also Citrix's commitment to Desktop delivery of highly bandwidth intensive applications can be observed from the adding the HDX support for Delivering Professional graphics applications over a 2Mbps WAN link.

OEMs and Partnerships to Strengthen the Weaker Arm:
While continuing to tirelessly innovate on Server Virtualization technologies, VMware has also been actively operating in the VDI space with VMware View. VMware has integrated the PCoIP technology from teradici and claims to have performances comparable to Citrix HDX. Managing User Profiles had been another drawback of VMware View and with the RTO Software OEM Deal, VMware has quickly added this capability to compete more strongly against XenDesktop.

Also Citrix has been actively partnering with Startups to offer management functionalities on top of the XenServer Virtualization platform. This is evident from the OEM of FT technology from Marathon and the LabManager and StageManager products from VMLogix.

Also Citrix has been engaging with the OpenSource community to build advanced capabilities on top of XenServer like the Xen Cloud Platform and the distributed vSwitch for XenServer/KVM.

It has been a very fierce battle between these two highly tech savvy companies and it is always good for the customers as long as there is such competition in the market. I don't believe one company is going to dominate the whole virtualization market. The adoption of Server/Desktop Virtualization technologies is definitely looking towards steep growth in the coming years and there is enough for these two giants and lots of other companies to share the pie.

Hypervisor Storage Integration - Is Citrix leading the Game?

Had posted in my previous post on the feature comparison between XenServer and ESX.

Apart from those, storage integration has been one area where Citrix has been leading the game. XenServer 5.0 has built in integration with NetApp and EqualLogic storage arrays. This enables XenServer to leverage the storage features like Snapshotting, Fast clone and thin provisioning.

Though this might not have a serious performance implications for normal workloads, this integration makes XenServer more suitable for disk intensive workloads and for apps like VDI and LabManager. Both VDI and Labmanager rely extensively on the fast clone and snapshot features. Offloading these functions to the storage should give users noticeable I/O performance enhancements and also free up CPU cycles on the Server. I am not aware of XenApp using the fast clone technology like VMWare View Manager does, but Citrix Labmanager (OEMd from VMLogix) extensively uses this feature and should be interesting to note the performance differences between VMLogix Labmanager on ESX and on XenServer with NetApp storage.

Citrix has gone another step further by introducing the new product - Virtual Storage Manager (VSM) for both XenServer and Hyper-V. This product integrates with the leading storage vendors and provides the capabilities to carve out LUNs on the arrays on demand and present them to the hypervisors. This should fill the gap with the non-availability of Cluster file system in Hyper-V. Being a 1.0 product, it seems to lack functionalities in terms of the no. of storage vendors it supports and also support for Zoning of the FC switches. But this definitely is an interesting product to watch out for.

In my view VSM should boost the virtualization of I/O intensive production apps. By mapping storage LUNs straight to the VMs, you can provide the same performance and reliability to the VMs as that of physical machines. By automating and integrating storage provisioning with the hypervisor tools, Citrix has given the flexibility to quickly provision the VMs On Demand.

VMWare is definitely not lagging far behind. VMWare has announced the vStorage framework for integrating drivers and features specific to storage vendors into ESX 4.0. Should be interesting to watch if VMWare can come out with a broader vendor support and more features compared to Citrix in vStorage.

Let's wait and watch.