

Tilton's Law - solve the first problem first - bdfh42
http://smuglispweeny.blogspot.com/2008/03/tiltons-law-solve-first-problem.html

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yummyfajitas
Quite right.

A client (back when I was a teenage "computer hacker", fixing people's
computers for pizza money) had the problem that her computer was unstable. It
would shut down at random times. Printing stuff _at night only_ would do it;
shortly after printing, the computer would shut down. Also, it would shut down
when it was cold, and only restart when the house was warm. And while things
would be fine if she was using it, it would turn off if she went off to do
other things (e.g. iron her clothes).

Hard to diagnose, but a wild guess: power issue. Lets try swapping out the
power supply.

The __real __first problem: unplugging it. There was a single outlet, with a
red/black tree of power strips/extension cords plugged into it. Not just
computer equipment, it was also plugged into a space heater, air conditioner,
alarm clock, coffee maker, etc.

After plugging all the crap into a different outlet, I unplugged the computer
and opened it up. Didn't have a power supply with enough watts. Promised to
get back to her in a day or two.

When I called her back, everything was fine. The "teenage hacker" solved her
computer problem, stopped her lights from flickering, and made her alarm clock
stop turning off whenever she vacuumed.

The problem: 1 socket, about 3000 watts. When it got cold, she turned the
space heater on. Computer drained of power, switches off. Print something at
night, switch on a 500 watt halogen lamp, computer shuts off.

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jkkramer
An interesting counterpoint -- or at least, a tempering perspective -- is the
story that made the rounds recently about a consultant who was called in to
fix an unstable Linux kernel driver:

The company programmer was slavishly fixing each symptom as it popped up
during boot -- that is, each "first problem" he saw. The consultant instead
took a look at the code from a holistic perspective, and was able to fix the
root cause.

So while sometimes the temporally-first problem is the root cause, sometimes
it's just a symptom. Look for the _logically_ first problem which precipitates
the symptoms.

