This is a great site which lists the “interesting” properties of a whole bunch of number from 0 to 9999. Here are the first few entries:
0 is the additive identity.
1 is the multiplicative identity.
2 is the only even prime.
3 is the number of spatial dimensions we live in.
4 is the smallest number of colors sufficient to color all planar maps.
5 is the number of Platonic solids.
6 is the smallest perfect number.
7 is the smallest number of faces of a regular polygon that is not constructible by straightedge and compass.
8 is the largest cube in the Fibonacci sequence.
9 is the maximum number of cubes that are needed to sum to any positive integer.
10 is the base of our number system.
11 is the largest known multiplicative persistence.
Another (better?) study on disk reliability?
Slashdot has a new article which says:
Google’s wasn’t the best storage paper at FAST ’07.
Another, more provocative paper looking at real-world results from
100,000 disk drives got the ‘Best Paper’ award. Bianca Schroeder, of
CMU’s Parallel Data Lab, submitted Disk failures in the real world: What does an MTTF of 1,000,000 hours mean to you? The paper crushes a number of (what we now know to be) myths about
disks such as vendor MTBF validity, ‘consumer’ vs. ‘enterprise’ drive
reliability (spoiler: no difference), and RAID 5 assumptions.
StorageMojo has a good summary of the paper’s key points.
See full article and interesting comments.
Google releases paper on disk reliability
Slashdot is reporting on a just published a paper out of Google on Failure Trends in a Large Disk Drive Population.
Excerpts:
Based on a study of 100,000 disk drives over 5 years they find some interesting stuff. To quote from the abstract: ‘Our analysis identifies several parameters from the drive’s self monitoring facility (SMART) that correlate highly with failures. Despite this high correlation, we conclude that models based on SMART parameters alone are unlikely to be useful for predicting individual drive failures. Surprisingly, we found that temperature and activity levels were much less correlated with drive failures than previously reported.’
See full article.