

Virtualization and over-subscription: breaking the 100% utilization barrier - tsmith
http://blog.gridcentriclabs.com/2010/08/virtualization-and-over-subscription.html

======
jbz
I can still remember the first time I put together a vmware virtualcenter
server with a few servers running the hypervisor. It was the first time I
encountered software that left me speechless since it felt like it was built
with magic, at the time since I simply couldnt comprehend how this could be
done.

I ended up quitting the company I built it at because they didnt see the point
of virtualization and werent going to implement it.

~~~
amscanne
Indeed. Generally speaking, virtualization adoption hasn't set any speed
records. But slow and steady wins the race, as they say. :)

------
tsmith
Also of possible interest - things we've done with the current (1.1) version
of our platform:

Howto: Build and scale a Cassandra cluster in five minutes -
[http://blog.gridcentriclabs.com/2010/08/howto-build-and-
scal...](http://blog.gridcentriclabs.com/2010/08/howto-build-and-scale-
cassandra-cluster.html)

Howto: Build a Hadoop cluster in five minutes -
[http://blog.gridcentriclabs.com/2010/07/howto-build-
hadoop-c...](http://blog.gridcentriclabs.com/2010/07/howto-build-hadoop-
cluster-in-five.html)

Howto: Build a ten node memcached cluster in five minutes -
[http://blog.gridcentriclabs.com/2010/07/how-to-
build-10-core...](http://blog.gridcentriclabs.com/2010/07/how-to-
build-10-core-memcached-cluster.html)

You may notice an interesting trend :)

[edit: formatting]

------
patrickgzill
Actually OpenVZ already has a lot of the things mentioned, although only for
Linux VMs running on top of an OpenVZ-ified Linux kernel.

Paging, ballooning, content-based sharing, CPU and RAM overcommit, all are
there, provided you only use Linux VMs.

~~~
tsmith
Good point - OpenVZ is quite good for userspace virtualization.

One thing Copper (what this demo is running on -
<http://www.gridcentriclabs.com/copper>) can do that OpenVZ can't do is VM
clone / page sharing across multiple physical servers. For example, if you
wanted to clone thousands of desktops across a rack or two of servers.

