Revisiting the Five-Minute Rule

In 1987, a study published by Jim Gray and Gianfranco Putzolu evaluated the trade-offs between holding data in memory and storing it on a disk. Known widely as the "five-minute rule," their research was updated and expanded 10 years later. Now, as jamie points out, Communications of the ACM is running an article by Goetz Graefe with another decennial update, evaluating the rule using hardware and software typical of 2007, with an eye toward how flash memory will affect the situation. An excerpt from Graefe's conclusion: "The 20-year-old five-minute rule for RAM and disks still holds, but for ever-larger disk pages. Moreover, it should be augmented by two new five-minute rules: one for small pages moving between RAM and flash memory and one for large pages moving between flash memory and traditional disks. For small pages moving between RAM and disk, Gray and Putzolu were amazingly accurate in predicting a five-hour break-even point two decades into the future. Research into flash memory and its place in system architectures is urgent and important. Within a few years, flash memory will be used to fill the gap between traditional RAM and traditional disk drives in many operating systems, file systems, and database systems."

Comments

Re:OS patches?

[Runaway1956]

MSDN? Noted. The author of that article has a vested interest in an operating system prone to such exploits. He makes use of chmod in Linux to make a point - but he fails to note that the Linux user is somewhat less likely to a: have admin rights or to b: grant admin rights to a program if he has them.

Dancing bunnies indeed. When I look at bunnies, I see food. (actually, they are catfood or dogfood more often than they find their way onto my table) I don't have any desire to see food dance.