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How to manage your time more effectively (according to machines) - Brian Christian

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    In the summer of 1997,
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    NASA's Pathfinder spacecraft landed
    on the surface of Mars,
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    and began transmitting incredible,
    iconic images back to Earth.
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    But several days in,
    something went terribly wrong.
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    The transmissions stopped.
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    Pathfinder was, in effect,
    procrastinating:
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    keeping itself fully occupied
    but failing to do its most important work.
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    What was going on?
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    There was a bug, it turned out,
    in its scheduler.
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    Every operating system has something
    called the scheduler
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    that tells the CPU how long
    to work on each task before switching,
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    and what to switch to.
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    Done right, computers move so fluidly
    between their various responsibilities,
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    they give the illusion
    of doing everything simultaneously.
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    But we all know what happens
    when things go wrong.
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    This should give us, if nothing else,
    some measure of consolation.
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    Even computers get overwhelmed sometimes.
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    Maybe learning about the computer science
    of scheduling
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    can give us some ideas about our own
    human struggles with time.
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    One of the first insights is that all
    the time you spend prioritizing your work
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    is time you aren't spending doing it.
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    For instance, let's say when you check
    your inbox, you scan all the messages,
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    choosing which is the most important.
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    Once you've dealt with that one,
    you repeat.
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    Seems sensible,
    but there's a problem here.
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    This is what's known
    as a quadratic-time algorithm.
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    With an inbox that's twice as
    full, these passes will take twice as long
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    and you'll need to do
    twice as many of them!
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    This means four times the work.
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    The programmers
    of the operating system Linux
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    encountered a similar problem in 2003.
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    Linux would rank every single
    one of its tasks in order of importance,
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    and sometimes spent more time
    ranking tasks than doing them.
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    The programmers’ counterintuitive solution
    was to replace this full ranking
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    with a limited number
    of priority “buckets.”
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    The system was less precise
    about what to do next
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    but more than made up for it
    by spending more time making progress.
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    So with your emails, insisting on always
    doing the very most important thing first
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    could lead to a meltdown.
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    Waking up to an inbox three times fuller
    than normal
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    could take nine times longer to clear.
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    You’d be better off replying
    in chronological order, or even at random!
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    Surprisingly, sometimes giving up
    on doing things in the perfect order
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    may be the key to getting them done.
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    Another insight that emerges
    from computer scheduling
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    has to do with one of the most prevalent
    features of modern life: interruptions.
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    When a computer goes
    from one task to another,
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    it has to do what's called
    a context switch,
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    bookmarking its place in one task,
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    moving old data out of its memory
    and new data in.
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    Each of these actions comes at a cost.
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    The insight here is that there’s
    a fundamental tradeoff
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    between productivity and responsiveness.
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    Getting serious work done
    means minimizing context switches.
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    But being responsive means reacting
    anytime something comes up.
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    These two principles
    are fundamentally in tension.
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    Recognizing this tension allows us
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    to decide where
    we want to strike that balance.
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    The obvious solution
    is to minimize interruptions.
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    The less obvious one is to group them.
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    If no notification
    or email requires a response
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    more urgently than once an hour, say,
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    then that’s exactly how often
    you should check them. No more.
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    In computer science, this idea goes by
    the name of interrupt coalescing.
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    Rather than dealing with
    things as they come up –
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    Oh, the mouse was moved?
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    A key was pressed?
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    More of that file downloaded? –
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    the system groups these
    interruptions together
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    based on how long they can afford to wait.
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    In 2013, interrupt coalescing
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    triggered a massive improvement
    in laptop battery life.
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    This is because deferring interruptions
    lets a system check everything at once,
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    then quickly re-enter a low-power state.
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    As with computers, so it is with us.
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    Perhaps adopting a similar approach
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    might allow us users
    to reclaim our own attention,
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    and give us back one of the things
    that feels so rare in modern life: rest.
Title:
How to manage your time more effectively (according to machines) - Brian Christian
Speaker:
Brian Christian
Description:

View full lesson: https://ed.ted.com/lessons/time-management-brian-christian

Human beings and computers alike share the challenge of how to get as much done as possible in a limited time. Over the last fifty years or so, computer scientists have learned a lot of good strategies for managing time effectively — and they have a lot of experience with what can go wrong. Brian Christian shares how we can use some of these insights to help make the most of our own lives.

Lesson by Brian Christian, animation by Adriatic Animation.

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Video Language:
English
Team:
closed TED
Project:
TED-Ed
Duration:
05:10

English subtitles

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