Context switches are expensive

Anyone who is familiar with how operating systems manage multitasking knows that context switches are expensive. But that's nothing to how expensive context switching is in humans[1].

This morning I wanted to consult with a coworker about an important but low-urgency issue, so I went to my IM contact list ... and discovered he wasn't logged into IM. I didn't want to interrupt him (low urgency) but did want his input (important issue). So I dialed his desk on the intercom: "Ruks, are you interruptable?"

Turns out this sort of tiered communication is pretty common. Shortly after consulting with Craig, I spotted an article[2] reporting on research done by Ohio State University and the University of California that found exactly this.

It seems that workers use instant messaging to reduce interruption.. in place of phone calls and showing up at each others' desks. This reduces context switching, and consequently increases productivity.

One of the study's authors thinks that IM won't be as widely adopted as email. I'm not convinced; there are 2.4 billion SMS text users in the world[3], or 74% of all mobile handset users, while the there are just 1.2 billion email users worldwide[4]. While there are "only" 67 million "enterprise" IM users, I think the massive adoption of SMS — a form of instant messaging IM that happens not to be PC-based — gives the lie to the idea that IM doesn't have the same traction as email.

Given the inordinate amount of time we waste on email every day — consuming up to 25% of our workday[5] — I see the adoption of IM in business as a hugely good thing.

IM seems to not only reduce that email load but make us more productive... that's some nice icing on that cake.

Now, if you'll excuse me, I need to go interrupt a coworker...