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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:

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

English subtitles

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