I just read through the data sheet of a 4TB Seagate hard drive which says "Nonrecoverable Read Errors per Bit: 1 sector per 1014. Guess that's none better or worse than any other harddisk's error rate, only maybe you've never looked or the manufacturer doesn't publish it.
Anyway, this got me thinking, 1014 bits is only about 11.5 terabytes. It's a 4TB disk. Therefore, assuming you fill this disk using its complete capacity, there is an 1/3 chance that you have an unrecoverable defect sector. After only one complete write cycle? Note that the emphasis is on "nonrecoverable", I am certainly aware that one or the other bit may always flip by accident, that's just how things work -- but the drive's FEC will routinely correct that.
If you do 3 complete write cycles, you are statistically more or less guaranteed to have at least one nonrecoverable defect sector. Not seriously?
I must have some fallacy in my reasoning? Surely harddisks must despite all be a little more reliable than to allow 3 write cycles?
Edited by samoth, 07 November 2013 - 11:03 AM.