

Ask HN: why don't larger cloud hosts use container virtualization? - api

I've used container-based virtualization for Linux (OpenVZ / Parallels Virtuozzo) before and it's rather amazing performance-wise. Performance is bare metal, and the densities that can be achieved are staggering and easily destroy any density achievable with paravirtualization. In addition, OpenVZ/Parallels supports container migration and it works flawlessly in my experience.<p>(When I say destroy I mean destroy. I have seen thousands of containers on a single node that would support a few dozen KVMs.)<p>The only downside I can see is the lack of custom kernel capability, but that only affects a tiny percentage of applications. (None in many configurations.)<p>I'm curious as to why Amazon, Linode, Rackspace, etc. do not offer container-based virtualization. Is there some Big Reason?
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jrarredondo
We use it at Rackspace under our Cloud Databases service. Check this out (high
level)

[http://c1776742.cdn.cloudfiles.rackspacecloud.com/downloads/...](http://c1776742.cdn.cloudfiles.rackspacecloud.com/downloads/pdfs/Rackspace-
Cloud-Databases-and-Container-based-Virtualization.pdf)

I think one reason it is not more common is because there are fewer people
with expertise and it is more sophisticated (read complex).

