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Comment by Simucal | Hacker News Reader

I went to this university and took several of Professor Cooper's classes. He was a great guy and he seemed really passionate about his Mersenne project.

One thing that was annoying however was the prime finding software was put on every lab computer possible. It was suppose to pause when a user got on a machine and resume when they got off. This seemed to never be the case though because they would all run terribly slow and when you checked the process list the prime software would be pegging the CPU. After reporting the problem several times I simply added a line in my bash file to kill it when I logged on.

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David McOwen was a tech who installed distributed computing clients on the machines in his lab.

(http://www.securityfocus.com/news/300)

> A computer network administrator faces multiple felony charges and years in a Georgia prison for allegedly installing Distributed.net clients without permission. Prosecutors say its justice, others aren't so sure

> A college computer technician who offered his school's unused computer processing power for an encryption research project will be tried next month in Georgia for computer theft and trespassing charges that carry a potential total of 120 years in jail.

> The closely-watched case if one of the first in which state prosecutors have lodged felony charges for allegedly downloading third-party software without permission.

What a lot of people missed was the significantly raised electricity bills from having 500 PCs running this software all day.

And a gorgeously authentic 2001 page (http://freemcowen.com/)

He ended up getting a year of probation (http://www.freemcowen.com/thelatest.htm).

Facing a huge prison sentence for "hacking"... sounds eerily familiar. >sigh<

That's sounds familiar. I went to a university where the one professor that was using Linux (and his knowledge was very little) was constantly tying up the Linux machines in our labs to run his prime number generation tool.

His research was into finding a faster/easier way to do prime number factorization in an attempt to speed up cryptography of any kind that uses it. Part of that was finding an easier/faster way to compute prime numbers in the first place. It was fascinating stuff ... but those machines were useless for anything but doing those calculations since it was using up all cores/HT's.

My university's physics department did the same thing with SETI@home. The SETI@home guys were smart enough to make their program run as a screen-saver that displayed Fourier Transforms so people thought it made the lab look more sciency and left it on.

Another important note is that SETI@home actually did stop running when you were using the PC. If you left Task Manager up, you could see the difference on the CPU usage graph.

and that's why they didn't find any alien intelligence yet

What OS was this? Processes like these (Folding, Seti, etc) should be "niced" on *nix-like OSes to have the lowest possible priority. Not sure what this looks like on Windows, but I imagine it's possible.

In windows, each process has one of 6 priority levels, and each thread has one of 7 priority levels. The combination is looked up in a table and yields one of 22 values between 1 and 31. http://msdn.microsoft.com/en-us/library/windows/desktop/ms68... You can manually change priority levels by right-clicking a process in the Task Manager. Not sure how to do it automatically or on a command line.

Edit: note the OS will "boost" priorities on certain processes or threads sometimes. http://msdn.microsoft.com/en-us/library/windows/desktop/ms68...

nice doesn't help with I/O pressure or memory contention, particularly if it used enough memory to contribute to swap activity. Even something like pressure on the system L2/L3 caches can be a big deal, particularly on older systems where those were less generous.

Thats where ionice or, even better, cgroups[1] come in :)

[1] http://en.wikipedia.org/wiki/Cgroup

Agreed, although I would note that at least on Linux and FreeBSD those haven't been a realistic option for a terribly long period of time – if the user didn't go to school recently, it's likely that they weren't an option.

(also, not sure about cgroups but ionice did absolutely nothing useful with swap churn when I tested it awhile back)

After reporting the problem several times I simply added a line in my bash file to kill it when I logged on.

It would have been discovered sooner if you hadn't done that. :)

why on earth would they run it as you user?

Several of us had root access to the few Linux boxes in the CS computer lab.

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