The Green Software Unconference is scheduled for August 19 at the Computer History Museum in Mountain View, CA. Since this is an unconference, there is no set agenda or program. But its theme is clear: What is green software and what can we do with it?

As everyone knows, IT includes many elements, such as hardware, software, systems, services, and staffs.  Yet, when it comes to green IT, most of the focus has been on hardware. For example, one aspect of green IT is to cut power consumption. When you consider the power consumption of IT equipment, you measure power consumption by hardware devices, such as servers, even though hardware devices consist of both hardware and software. Most discussions have centered on how to make hardware devices more energy efficient. The well-known data center metric PUE (power usage effectiveness) primarily concerns hardware. The newer and supposedly better metric DCeP (data center energy productivity) still measures hardware performance alone, although software running on a hardware box may make a big difference in energy efficiency.

Why this is the case? It is very simple: there is no easy way to measure software energy efficiency. Hardware is a physical entity that you can see and touch. If you power it up, you can see it in action with pilot lights and screen display, and you can hear the clicking of the rotating disk(s). On the other hand, what about software? Can you see or touch it? Yes, you can take a look at the source code on a display or on paper. But that is a form that is easier for humans to understand and may not be the real software. Software is an electrical signal in the working IT device, telling hardware components what to do. This is why programming is so hard. What you see on the screen or on paper (the source code) is not the same as the dynamic electrical signal, which you cannot see, in action. I programmed a lot some years ago and know this firsthand. What you see in the static code is sometimes totally different from how the code behaves, and thus, it is very hard to debug it.
Software can be made more energy efficient.

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Solution Brief: Building MPLS+ Managed Services
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These are some of the things we can consider:

• Parallel programming—hard to program, nondeterministic (such as race condition)
• Design/architecture—modularized structure vs. big monolithic chunk (e.g., SMTP server)
• Interpretive vs. compiled—web languages vs. C, C++, and Java
• Performance vs. ease of use—heavy on the ease of use and leave the heavy lifting to hardware
• Optimization—optimizing compilers and other utilities

Those and other solutions are to be discussed.

Another subject AltaTerra will propose at the unconference is monitoring and measuring power consumption. This relates to the carbon footprint and IT. The carbon footprint as it relates to IT will be discussed by our co-founder and president, Don Bray, who is an expert in carbon management.

I will cover what monitoring and measuring (and thus, metrics) have to do with green software. This is an example of how to make other things greener with software. I covered this subject in the previous blog.

Power consumption is like software. You cannot touch, hear, or see it. Traditionally, IT managers do not see, much less review, the electricity bills for their data centers. Showing power consumption information continuously in real time and making it available to IT managers and executives would make IT folks aware of power consumption and encourage them to attempt to reduce it. Even a good idea, no matter how simple it is, needs a lot of time to sink in with practitioners. I confirmed it with Sentilla, which develops and markets monitoring and measuring solutions for data centers and other buildings. There are still a lot of data center operators who have not started monitoring and measuring their power consumption.

The power consumption information is a precursor to carbon management because there is no immediate way to measure GHG emissions. So if you do one single thing to green your data centers, it has to be to start monitoring and measuring power consumption.

In summary, AltaTerra will propose three subjects at the Green Software Unconference: making software greener, making other things greener with software, and carbon management through software. I am looking forward to meeting you there and discussing these and other important issues regarding green software.

Tags: Data Center, Green IT, Green Software