“How we spend our days is ,of course, how we spend our lives.”——Annie Dillard ,The Wirting Life

In the summer of 1997, NASA’s Pathfinder spacesraft landed on the surface of Mars, and began transmitting incredible , iconic images back to Earth. But several days in ,something went terribly wrong . The transmissions stopped. Pathfinder was, in effect, procrastianting: keeping itself fully occupied but failing to do its most important work. What was going on ? There was a bug, it turned out, in its secheduler.

Every operating system has something called the scheduler that tells the CPU how long to work on each task before switching , and what to switch to. Done right, computers move so fluidly between their various reponsibilities, they give the illusion of doing everthing simultaneously . But we all know what happens when things go wrong.

Maybe learning about the computer secience of scheduling can give us some ideas about our own human struggles with time.
One of the first insights is that all the time you spend proiritizing your work is time you aren’t spending dong it .

For instance, let’s say when you check your inbox, you sacn all the messages, choosing which is the most important . Once you’ve dealt with that one ,you repeat. Seem sensible, but there 's a problem here. This is what’s known as a quadratic-time algorithm(二次時間演算法). With an inbox that’s twice as full, these passes will take twice as long and you’ll need to do twice as mang of them ! This means four times the work.

The programmers of the operating system Linux encountered a similar problem in 2003. Linux would rank every single one of its tasks in order of importance, and sometimes spent more time ranking tasks than doing them. The programmers’ counterintuitive solution was to replace this full ranking with a limited number of priority “buckets”. This system was less precise about what to do next but more than made up for it by spending more time making progress.

So with your emails, insisting on always doing the very most important thing first could lead to a meltdowm. You’d better off replying in chronlolgical order, or ever at random ! Supersingly , sometimes giving up on doing things in the perfect order may be the key to getting them done.
Another insight that emerges from computer scheduling has to do with one of the most prevalent features of modern life: interruptions.

When a computer goes from one task to another, it has to do what’s called a context switch(上下文切換）: bookmarking its place in one task, moving old data out of its memory and new data in .

The obvious solution is to minimize interruptions. The less obvious one is to group them. If no notification or email requires a reponse more urgently than once an hour, then that’s exactly how often you should check them. No more. In cmputer secince, this idea goes by the name of interrupt coalescing(中斷合併). In 2003 , interrupt coalescing triggered a massive imprevenent in laptop battery life. This is baceuse deferring interruptions ,lets a system check everthing at once, then quickly re-enter a low-power state.

As with computers ,so it is with us. Perhaps adopting a similar approach might allow us users to reclaim our own attention, and give us back one of the things that feels so rare in modern life :rest