[deepsun]

Sure. By "really-work" I mean thinking of work and doing it, not just being at work.

I, personally, rarely can do really-work more than 4 hours a day -- only if task is very interesting and challenging. Then I can do it for 12 hours a day straight, but I stop myself if I work more than 6 hours, because I know I would burn out, happened a few times.

4 hours a day of really-work sounds not a lot, but my performance is pretty good comparing to my teammates. Never heard managers complain on my performance. The other 4 hours I spend on meetings/lunch/hacker news/socializing etc. So I would look for a candidate who can do it for at least 4 hours a day.

I heard rumors of people who can really-work for 8 hours a day (like John Carmack). Those people are called "100x engineers", I really want to work with some of them one day.

[0xfeba]

Well, I feel better for only doing ~4 hours of real work then. I take breaks often for socializing/HN/car forums. Plus meetings and interruptions.

But I can produce just as much as some other developers, so I really see no incentive to do more work unless it's clear I will get more recognition for it, rather than just more work to do.

[fpisfun]

I can definitely really work for 8 hours a day if it's on my own project and I'm in the flow but no way I can ever get in they mindset to do it for an employer, especially that I have a less than spectacular salary, I'm guessing many people are the same way.

[codycraven]

I can easily work 8 hours per day straight, however throw two or three interruptions into my day (meetings or the like) and I'm lucky if I can get back in a solid flow. Put me in three hours of meetings and I'm completely toast from that point on.