Multitasking

Concentration is important! Long periods of uninterrupted focus are crucial to getting some things done. Writing code, for instance, or documentation, or composing some detailed email about how to solve parking problems. But sometimes, if you were to concentrate on just one thing at a time, you'd spend a lot of time waiting, and waiting, and waiting.

For instance, compiling a piece of software, or even refreshing your local checkout of your project's version control system. Talking via instant messenger with someone can also qualify; while chatting is one thing, sometimes IM is used for serious work-related discussions, and you need to frequently make sure you're keeping up with your part of the discussion. Polling your inbox can also qualify, especially if you're waiting for an important email (such as a response to a network ticket you've filed, or the day's lunch menu).

The key to successful multitasking is getting as much state out of your brain and into the computer. Front-load the thinking and decision making, and then spread yourself as thin as possible across multiple tasks. The goal is that, given some pile of tasks, you quickly dispatch the next step in each one as soon as it is ready.

Another key is to be able to quickly recover state if you've lost it. Sometimes, power outages happen, or you have to go home, or your network filer decides it really, really needs to stop talking to the network for a while. Good multitasking hygiene means it is as easy as possible to pick up where you left off, be it five minutes or five days later.

For me, one of the most common multitasking challenges is waiting for various programs to finish. Sometimes I'm working on some code that needs compiling (usually C++). Compiling can take a while. Instead of sitting there and waiting for my terminal to finish the compile, I switch to another desktop. Likewise, when running some tool that talks to other services over the network, there can be a delay. Don't just sit there waiting, go find another desktop and work from there.

Assuming you have a few different desktops with various tasks running on them, though, you sometimes can lose track. There are a few strategies for dealing with this. One is to graze across your desktop and windows, looking for completed tasks. I used to do this a lot, but it is easy to forget desktops. Lately I've been using xosd to pop-up unobtrusive onscreen messages when programs complete. This is nice in that it gets my attention without being too obnoxious.

I actually extended that idea into a little script that continuously polls /proc for known long-running processes (make, version control checkouts, etc). When it sees one live over a few seconds, it will automatically send an onscreen display when it completes. I'll probably teach it to do the opposite -- send a message when something has taken too long (such as leaving a vi editing a version control checkin message for days instead of the checkin finishing... oops!).

Recovering state and being able to resume what you're working on is very important, too. Phones ring, coworkers drop by, and all sorts of other undeferrable interrupts occur during the day, some of which may pull you away for hours. The unix tool screen can help resume long-running jobs from different locations, which helps for some activities (long-running scripts you want to go home while they run, for instance). Also, taking notes of things to get back to, even if it is just a few minutes away, helps quite a bit (I permanently keep my todo file open, but I'm a luddite; software organizers and such work, too. The key is that you be incented to use it often and have no overhead in using it, which rules out things like PDAs).

Multitasking ends up being like juggling. You really are in contact with each ball (task) for a fraction of a second, but that fraction is enough to keep it in motion for much longer and until it needs your attention again.