Slashdot stories can be listened to in audio form via an RSS feed, as read by our own robotic overlord.

 



Forgot your password?
typodupeerror
Image

The Perfect Way To Slice a Pizza 282

Posted by samzenpus
from the equal-distribution-of-the-pie dept.
iamapizza writes "New Scientist reports on the quest of two math boffins for the perfect way to slice a pizza. It's an interesting and in-depth article; 'The problem that bothered them was this. Suppose the harried waiter cuts the pizza off-center, but with all the edge-to-edge cuts crossing at a single point, and with the same angle between adjacent cuts. The off-center cuts mean the slices will not all be the same size, so if two people take turns to take neighboring slices, will they get equal shares by the time they have gone right round the pizza — and if not, who will get more?' This is useful, of course, if you're familiar with the concept of 'sharing' a pizza."
Transportation

Computers Key To Air France Crash 911

Posted by kdawson
from the who-or-what-do-you-trust dept.
Michael_Curator writes "It's no secret that commercial airplanes are heavily computerized, but as the mystery of Air France Flight 447 unfolds, we need to come to grips with the fact that in many cases, airline pilots' hands are tied when it comes to responding effectively to an emergency situation. Boeing planes allow pilots to take over from computers during emergency situations, Airbus planes do not. It's not a design flaw — it's a philosophical divide. It's essentially a question of what do you trust most: a human being's ingenuity or a computer's infinitely faster access and reaction to information. It's not surprising that an American company errs on the side of individual freedom while a European company is more inclined to favor an approach that relies on systems. As passengers, we should have the right to ask whether we're putting our lives in the hands of a computer rather than the battle-tested pilot sitting up front, and we should have right to deplane if we don't like the answer."

Comment: Re:Raise taxes - but who will pay? (Score 1) 1505

Which can afford it? All of them!

Corporations are taxed on profits, not on revenue. So anyone who will be taxed by definition has money, because they made a profit. Remember, they can write off just about anything that is involved with the operation of the corporation. So if they're losing money, they don't pay taxes.

Contrast that against income taxes, which are mostly (with the exception of a couple of write-offs like mortgage interest) on revenue.

An interesting thought experiment... what if income tax was treated the same way as corporate tax... you can write off ANYTHING that has to do with operations (living your life). That would be quite a stimulus, because it would encourage people to spend on all sorts of things, rather than just on real estate.

Comment: Buy an appliance (Score 2, Informative) 298

by hitchhikerjim (#27040387) Attached to: Best Solution For HA and Network Load Balancing?

Your needs for 1000+ uniques are minimal. If I were to do it, I'd get a shared hosting account someplace and move on. Shared hosting can handle *way* more than that.

But if high availability (limited downtime) is part of the requirements, I'd say go out and buy an F5 BigIP. You plug your internet in the front, your machines in the built-in switch, configure your domain names in it using the web interface, and you're done. Set it to do service-checks, and it'll automatically pull out of the pool any machine that fails or that you take down for maintenance. So you get full up-time so long as your power and network don't fail.

Yes, you can get the same functionality using Linux HAProxy. But you sort of need to understand what you're doing. Reading the way your question is asked, I suspect you're learning this, and do you really want to make the mistakes on a real live project? Just go with the appliance until you have a solid understanding of what you're doing. Shoot -- I have a good solid understanding from years of experience, and I still use the BigIP when I have a budget (and HAProxy when I don't). It's just easier, and I can move on to more interesting problems with my time.

Once you've got this setup, set up a cron job to rdist the site to all the machines so that all your data is always on each machine. If you've got a database, you have some choices. For completely static data, I like to have it replicated to each machine, and have each web server just query localhost. If it's dynamic, have a replicated pair. At your levels, that can exist on the web servers.

I really dislike the cross-mounted disk architecture of traditional cluster solutions, because there are too many shared components. Each of those multiplies your possible points of failure for your whole setup. Better to keep everything completely separated, so if one component fails, that whole machine just drops out and the site keeps working because of the load balancer and because each machine can operate by itself.

Comment: Works great for me (Score 1) 575

by hitchhikerjim (#27035453) Attached to: Uproar Over Netflix's New Instant Viewer

When I changed to the Silverlight client, the quality improved, and I got to run it on my Mac too. What's not to like?

I love open source too... but you do yourselves a disservice when you fail to see the real reasons. They've got to stick to a DRM solution in order to get the film distributors to let them do rentals this way. It's how the distribution houses know who to pay royalties to. Without DRM, the major distribution houses would just say no. It's not Microsoft or Netflix forcing DRM on us -- it's the studios. And for a rental product (as opposed to a purchased one), it sort of makes sense.

Netflix planned this change for a year or more in order to deliver to the Macintosh market. They talked about it in their blogs and such -- they were just waiting for the Mac version of Silverlight to make it happen. I was sort of annoyed that it took so much longer than originally projected.

And for me the result has been significantly better quality with almost no re-buffering ever.

After any salary raise, you will have less money at the end of the month than you did before.

Working...