Amdahl’s Law is a principle in computer science describing where to best expend effort for maximal impact. This principle has applications everywhere.
None of this is financial advice. Always consult your financial advisor.
Amdahl’s law
The various engineering fields all have their principles, and many of them overlap often with different terminology. We tried to find Amdahl’s principle repeated elsewhere, but could not find a suitably generalized form to link from a previous article on being less wrong more often. Once seen, we’re tempted to call it “common sense,” but since we so often see people prioritizing and acting in contrary ways, we question how “common” this sense is.
Amdahl’s Law states that maximal impact can be obtained when the limited available resources are used to optimize the common case. Specifically, for (serial) computer programs, if 95% of the runtime of a computer program is spent doing Task A while 5% of the runtime is spent doing Task B, then spend your development time speeding up the code for Task A. If the developers instead spent their time happily optimizing Task B, then the most speed improvement you could ever see for their effort would be 5%.
This actually happens in real life. People spend a lot of their time optimizing Task B.
Drink less coffee
Personal finance is full of tips, tricks, and life hacks. One of the more typical bits of advice out there is to stop buying overpriced coffee on the way to work. Make your coffee at home instead, and in thirty years, you’ll be $150,000 richer. Any $5 savings, 250 times per year, invested at 8% gives a similar result after 30 years. At first glance, this is great advice!
So what’s the problem? For most people, 95% of their take-home pay is spent on big items like housing, food, car, and other fixed expenses. Maybe 5% is spent on little things we enjoy like coffee. Which should we optimize?
Marginal gains will accumulate. Small wins add up to big wins. There’s nothing wrong with saving $5 but ten times each day (over 30 years, that’s 1.5 million dollars). Amdahl’s law, when generalized, says to start with the 95%.
Smaller-sized or more modest housing, perhaps with a roommate, packs the biggest punch. This single change will turn a house-poor person into someone with lots of financial wiggle room. Gently used practical cars will save hundreds each month compared to something new and excessive. We often see oversized and overpriced pickup trucks in urban and suburban areas, which only makes sense if you dislike having money.
It’s not hard to cut your cell phone bill in half for the same service. By all means, cancel the subscriptions you don’t use. But first (or in parallel), the biggest savings can only come from the largest expenditures. For maximal impact, optimize the common case (first).
Breath easy
If 95% of the planet’s pollution comes from wasteful people living frivolous lifestyles, but only 5% of the pollution comes from everyone else, then maybe don’t make yourself miserable for a meaningless gain. That is an exaggeration, but it hints at what’s happening.
Imagine 70% of the government’s budget is entitlement spending which no elected official will ever touch. Just kidding, never mind.
When 95% of your workday is meaningless busy work, but you’re lucky if you have time for the remaining 5% that contributes to the health of the company, then you know your role is not designed to provide maximal impact. Once you realize this, you can look for a better job or simply enjoy the ride consciously.
The 80/20 principle often dovetails nicely into this principle. If 20% of your customers provide 80% of your profit, consider spending more time on the profitable 20% of your customers. Why do the other 80% generate so little profit? Can it be helped? Are you missing a new market? Or does it instead make sense to stop servicing them? Wouldn’t it be nice to free up 80% of your day but only at the cost of 20% of the pay? What if you can do something more productive or more enjoyable with that 80% of your time? Talk about leveraging your time for maximal impact!
Achieve maximal impact for your effort
Examine your expenditures, whether it be time-based, money-based, or effort-based. List out the items along with the percent of available resources being consumed or expended. Sort from highest to lowest, and attack the biggest offenders first. Optimize the common case. Work on the 95% line items before the 5% line items.
Effort doesn’t have to mean physical effort. Often our most impactful work is cleaning up our vibration.
Softening resistance for maximal impact
What do you spend the most time thinking about? Where do you feel the most lack? What puts you in a bad mood most often? These are the places where reworking our thoughts can have the biggest impact.
If we could, we would make a list of the things that trouble us most. We would sort the list decreasing by how often the subjects come up in our thought process but also how badly they feel when they do come up. Finally, for maximal impact, we would address the items that come first until we get them into better-feeling places. Alternatively, we would remove the reminders of those subjects from our daily experience, if that’s simple to do (i.e. remove a picture, ignore the news, etc), so that the topic comes up less frequently. Another option, often recommended by Abraham, is to direct your thoughts only or mostly toward those better-feeling topics that aren’t on the list.
Utilizing generalized Amdahl’s law for a cleaner vibration is a double productive use of effort. First, you’re addressing the underlying vibrational cause of whatever you’re trying to fix in your life. But also, you’re addressing your most negative vibrational responses in the order that helps you most. Sure, this is the approach for maximal impact, but it doesn’t even need to be this formal. If we simply recognize negative emotion when it happens, we can often take a moment to soothe it into a better feeling place. When we do this long enough, we might notice the items we address most often would have been highest on the list. Paying attention to how we feel automatically positions us for maximal impact.
