Ok, I bit. What does "Mean time to Data Loss" really mean? It's just a graph showing that two lines go down and the number of drives goes up. They both go down. But this useless marketing article never says why.
So I went and found the paper, which is here: https://www.usenix.org/legacy/events/hotstorage10/tech/full_papers/Appuswamy.pdf for your reading pleasure. I also note that the same hot topics conference has the paper: Mean Time to Meaningless: MTTDL, Markov Models, and Storage System Reliability Kevin M. Greenan, ParaScale, Inc.; James S. Plank, University of Tennessee; Jay J. Wylie, HP Labs" which you can find here: https://www.usenix.org/legacy/events/hotstorage10/tech/full_papers/Greenan.pdf This article makes a good case to me that MTTDL is useless. Not that I think their normalized time to dataloss metric is any more useful. And the Seagate article makes all these references, but then basically says "RAID is useless, use replication" which is just RAID1 at a distance with a delay in how quickly they are brought into sync. John _______________________________________________ Tech mailing list Tech@lists.lopsa.org https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
