minutia press.
Graft

I know I read in somebody's blog recently, and I thought it was Jim's about a trick to extend your CEC quota by having snapshot take pictures of a file that changes progressively. At the end, the series of snapshots can be a big file that exceeds your disk quota.

So I thought I'd tell a similar story about Rice, both because I think it's amusing but also to relate the power these kinds of ideas have on bad policy (low disk quotas at CEC for example).

When I arrived at Rice, I was surprised to find that all the student computing was "batch" (using punched cards you had to prepare offline) and that there were charges for disk space (15 cents per track per day). Moreover, because they did charge for disk space, you had to officiallly declare your willingness to pay for a file on disk by essentially filling out a form. Actually, you prepared yet another punch card with the name of the file and your account number.

At night, when not many people were looking, they would process those cards and any file *not* now or previously declared to be saved was backed up on tape and then erased from the disk. it was very common to forget to declare a file to be saved or to mistype the command to save the file. In either case, you'd find your file wasn't there the next day.

You could get it back, but they charged you $1.00 or so for that "service".

I didn't like this one bit (so to speak). I had better computing facilities in public high school in Dallas: timesharing and no silly policies about saving files on disk. In my sophomore year, I designed and implemented the project:

GRAFT -- Generalized Rice Archiving Facility to Tape

but (if you know me) there were some puns here. First, I was grafting files onto tape, but secondly, I was performing "honest graft" by cheating the disk-charging system. Here's how.

From a timesharing session you could indicate that you wanted a file saved by me, not by their version of CEC. Because this was done "online", I could check and make sure you really had a file by that name (no typos). When you saved the file with GRAFT, I also had a unix-like directory scheme for organizing your "back up" so you could easily find the file at some later point.

Every night, before the computer center's purge of unsaved files, I scheduled my job to run which would back up to my tape any file you wanted saved. Then, after their purge, I scheduled a job that would restore all GRAFT files back to disk. Result: free files, as much as you wanted. I had to pay for one tape and its storage, but that was dirt cheap compared to all the $$ we students were paying to save files.

Within a few weeks, the computer center changed its policy. I learned a valuable lesson: never underestimate the power of creative economics.



Comments

Now I won't feel guilty that I always look for ways to cheat the system... (not to be taken as "cheat" on a test or lab, but to look for shortcuts or loopholes in things)...

Did you get an honorary MBA from Rice after this?

Posted by: Ed at October 30, 2003 9:44 AM

Nope, they just gave me the BSEE degree

Posted by: rkc at October 30, 2003 10:59 PM

Looking over the current cost of a gig of drivespace, you'd come to the conclusion that CEC spends 15 cents per student on disk quota. My first reaction to this calculation was to run a starving ethiopian style fund drive. ("Just 15 cents buys an engineering student's drive quota for her entire career!" (Insert picture of dissheveled, plaintive looking student looking up into the camera.))

But that's not really accurate. The drives have to be housed in some kind of system to cover the rest of the SAN services, and there's always the cost of sysadminning. So I'm guessing that 50 cents is budgetted per student to drive quota. When I consider that the low quota (even after getting it increased about tenfold by multiple special requests) has held me back from doing projects for classes whose textbooks cost 100 times this much, and forced me to spend many times this much to set up replacement services on my home network... grr.

Posted by: Sam at November 6, 2003 12:11 PM

I'm on the CEC advisory board and exec committee this year and I'd like to bring your point to the attention of both of those bodies.

I do know that the original NetApp box CEC bought was very expensive, much more than say a software RAID. It's not clear that CEC would have trouble making a lot of disk space available though outside of a NetApp box.

Posted by: rkc at November 7, 2003 6:28 AM