Information Technology Reference
In-Depth Information
The True Definer of Cloud Computing
How do you make a cloud? What is the difference between a bunch of servers that are
connected together and a bunch of servers that are connected together through a high-
speed network and running separate OSs but have the ability to talk to each other through
standard messaging protocols like MPI or OpenMP? The difference is virtualization. To
give you a glimpse into the difficulty of qualifying this setting as a cloud, consider the
sidebar “Virtualization vs. Bare Metal.”
Virtualization vs. Bare Metal
Author Salman Ul Haq has recently been developing an image processing API that would
run on the cloud and would be able to process millions of images on the fly, performing
computer vision magic like giving you relevant tags for every photo you send to it based
on the content it analyses within the images. He went with Amazon to host his cloud
application.
Now suppose he deploys the application in a nonvirtualized environment, which would
essentially mean that each OS is physically consuming a single server (bare metal) and it
cannot run another OS instance on the same server at the same time. This would mean
that given Amazon had 10 servers and 10 users in total, including Salman, if he were to
need another “instance” or a machine to scale his application if his user base grew, then
he would need one physical server for every time he needed a new instance for scaling
his application.
What if 5 of those 10 users were not really consuming much resources and their servers
were sitting idle while the remaining 5 were humming at full capacity and needed more
server power? Multiply this by a million times or more and you get a glimpse into the
problem we would have if we just went with a bare metal, nonvirtualized cloud. It would
simply be infeasible. This is the primary reason virtualization is important. Simple market
economics are at work here: partitioning bare metal and enabling multiple OS instances
to run on the same server at the same time to increase user density and hence making
clouds commercially viable.
Serving the Whole World
Clouds come with the promise of delivering bottomless compute, storage, and networking
resources on demand. This has enabled small teams to smoothly scale their applications
Search WWH ::




Custom Search