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In Memoriam: Alex Vasilevsky – a Xen Pioneer

By August 9, 2010March 4th, 2019Uncategorized


On Sunday 8/8 the Xen Community lost one of its pioneers and staunch supporters, Alex Vasilevsky, to Cancer.   Alex was founder of Virtual Iron, which started out with a proprietary hypervisor and switched to using Xen in its later product releases.    When Virtual Iron was sold to Oracle (to become the core of what is now OracleVM), Alex founded Virtual Computer Inc., a vendor of virtual desktop solutions.
When I first met Alex, it was on the trade floor of Linux World in Boston, in mid 2005.   Virtual Iron was still developing its proprietary hypervisor, and Xen was just a hot open source community project with a fledgling startup being built around it.   So, notionally, Alex representing the proprietary world, and I represented the “threat” of the open source world – you’d have imagined that we would manage little more than a terse exchange to acknowledge our enmity.  But Alex, an incredibly warm and open man, took me aside and told me that he thought that Xen had a great future.  He wanted to know everything, including how he and his team could contribute to Xen.  He said “Even though we may compete in the market, I hope we can be friends,” and indeed that was what we became.   Alex and crew switched to using Xen some time later, and were wholly committed to Xen.org and the future of this community – and even though our products still competed in the market we remained friends and he played an important role in guiding the development and charter of xen.org.   He and his team  made important contributions to the runtime infrastructure of Xen, improving device models, management and stability.  They threw a huge amount of effort into testing and bug fixing.   And in the wonderful spirit of open source, those contributions live on, and always will, in the Xen code base, and in the products of all that use Xen – from Amazon Web Services to OracleVM, and to Citrix XenServer and many more.
In the summer of 2007, Alex had a vision that virtualization and client-side hypervisors could solve the age-old problem of managing Windows based PC’s. In December of that year, Alex co-founded Virtual Computer Inc. with the goal of making windows more manageable, more reliable and more secure while enhancing the end-user’s computing experience. Two and a half years later, that vision is alive and well and in the market in the form of Virtual Computer’s product called NxTop. This award winning product and its future revisions are a testimony to Alex’s entrepreneurship and vision that he brought to Boston area startups for the last 27 years.  NxTop uses Xen as a type-1 client hypervisor to deliver a paradigm shift in the delivery of virtual desktops.   The VCI team is a community development partner for the Xen Client Initiative.
Alex was a great innovator, an award winning scientist and entrepreneur, and most importantly a good father and husband,  and a trusted friend. He will be missed. We in the Xen community owe him a debt of gratitude for his vision, contributions, and hard work.  Even as he began to lose his fight against Cancer, Alex remained committed to his company and community because he passionately believed in its potential and the opportunity it offered to his family.
Simon Crosby, CTO, Citrix Systems