Better Know a VM: Part 1 of 435
(Originally posted on a shared blog that is now offline)
Every day we wake up to a new barrage of virtualization articles. I can't even read them all anymore, instead scanning headlines guided by statistical sampling (or is that stochastic?).
The hype is thick in the air, but it's not entirely unfounded. Somewhere in there we can see grid computing's going to be affected long term by OS virtualization in one way or another.
In this series we'll look at what's happening with various grid-VM efforts, often through a Globus lens (I work on the Globus Virtual Workspaces project so it's almost going to be impossible to avoid that).
There's a tradeoff between application performance improvements and developer time. Developers are expensive, development is time consuming. Perhaps it's worth waiting an extra few hours for results if it means you can start right now and stop paying those fine people. Obviously any particular calculation is going to be more nuanced than this, but I just wanted to set up an analogy.
In a similar vein, with virtualization you can take your prepared application+environment and get going on a new platform in minutes, not months. Cycles can be acquired and the exact compute environments can be provisioned out to the provider site's nodes. Resource consumption can be quantified well by the site (and even enforced at a fine grain). Less of the client's and site's administrators time (someone's money) needs to be spent on setup, environment conflicts, etc.
For all this you may take a small performance hit, but sometimes that's just worth it.
It sounds perfect, maybe. It's not quite, and we will look at a few problems, many of which only look temporary. A lot of progress is being made to get rid of the complexity, encapsulate it better, or factor it in such a way that the person/role who should be handling that complexity actually does (instead of it being unecessarily multiplied or divided across many people/roles).
Part 2? I'd like to talk about coordinating many VMs to work together, something being called contextualization. The fightin' Contextualization!
(Apologies to Stephen Colbert)