Juggling Molecules with Linux

An anonymous reader writes "This article at LinuxDevices.com describes an interesting project at the University of Vermont in which researchers use real-time Linux to build a laser trap that manipulates individual molecules by means of a computer-controlled laser beam. The project makes use of RTLinux, a real-time enhanced version of Linux that allows the system to process interrupts every 50 microsecond, sample new data, and timeshare the laser beam position. 'If the computer failed to respond, for even a millisecond, then we would drop the balls,' explained one of the researchers. Gives a whole new meaning to BSOD, eh?"

Re:Why do we have this statement?

[MarkByers]

I don't think it's paticularly a 'slam on Microsoft'. Imagine if the system crashed while a moecule was half-constructed and you had to reboot and start all over. Use the right tool for the right job.

There's nothing wrong with Windows as a games machine and for light word processing, but it's not suitable for everything. Maybe the submitter could have expressed themselves better.

Re:Realtime Linux on the desktop.

[digidave]

"What? Users like fast systems? What a breakthrough study!"

No, it turns out that users actually prefer trading off calculation speed for a quicker GUI. So even if doing a major spreadsheet export takes a few seconds longer, it's the speed of the menu, resizing windows, etc that makes a difference to them.

Re:Not sure about this..

[BGA]

Being RT means it has predictable response times. If some specific operation is said to take 10 ms to complete you can count that as being always true and this is what makes RT systems special. That's why it would be *VERY* difficult to have a "partial" RT system like what you decribe. Either it is RT or it is not.

That said, recently we had some flexibility on the Rt definition and we ended up with definitions for systems that are "hard RT" and "soft RT". The first case is what I described (QNX is hard RT, for instance). The second one is a system that provides extremelly low latency times but they are not really predictable, although the average time is (BeOS - now Zeta - is said to be soft RT).