Throughput funda's

I have been quite inconsistent in updating the information presented on this blog. The one things that discourages me like any other new blogger is that very little traffic is seen here and since this is a technical blog, unless i get feedback it is difficult for me to judge if something is good or bad. However, for now i have considered that no feedback is negative feedback. Nevertheless i continue to write.
What is Throughput...This is the weeks question.
Wordweb tells me

Output relative to input; the amount passing through a system from input to output (especially of a computer program over a period of time)

The Throughput that i am talking is the one that embedded engineers often talk about. In simple terms this value is a measure of the CPU load under the worst conditions. What could be the worst conditions? These are basically situations which demand more processing power. For example, Image Stabilization, Red Eye Detection, Smile Detection, Ambient light detection along with Click detection or auto timer ( and image post processing) in a Camera perhaps put a great deal of performance demands on the CPU in a Digital camera and this also determines it worst case performance.
Unfortunately like many other engineering terms a higher value of throughput means that your system is more loaded. Often under some conditions the throughput reaches 100% in systems which means the CPU has almost no idle time and is being utilized all the time to its maximum capacity.
If i look at it from an EMS perspective then startup is the when there is very high CPU loads that are encountered. In an OS based system there are methods to determine for how much time the CPU is free. Usually, some background tasks which are not necessary to be done all the time are done in this free time. ( Example, CRC calculation or RAM Checks etc). In simple scheduler based systems the throughput is just the time remaining in the baseloop after all the tasks have been finished. One more parameter that influences the throughput to a great extent is the Interrupt Rate. A very high interrupt rate will ensure that the CPU loses a lot of time in context switches which are really an overhead and do not contribute in anyway to the functionality of the system.
[ This was my understanding of Throughput. After looking into wiki i think the origin of is term comes from the CPU bandwidth utilization. The term is primarily used for parametrization of Communication channel bandwidths]

How Do we ensure that we never reach 100% throughput?

• Plan your interrupts and their sources well. You should know the worst case rate of an interrupt beforehand. Example, the Door lock engage interrupt cannot come at say more than 1-2 times a second ( Due to the inertia of the lock).
• Write your code with throughput in mind. E.g if possible use binary search in place of linear search. Use macros instead of functions judiciously
• Overuns should be detected in software using some special variables or debug variables. Over-Runs occurs when the throughput goes more than 100%. Which means that you have asked the CPU to more than it is capable of handling in the given time. 

This is very brief and windowed perspective of Throughput. If you have some other inputs as to how this is related to your domain then do put a few lines of comments.
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