[TUHS] Irwin 285
wb at freebie.xs4all.nl
Fri Jan 22 19:34:09 AEST 2010
Quoting Jochen Kunz, who wrote on Fri, Jan 22, 2010 at 10:14:24AM +0100 ..
> On Thu, 21 Jan 2010 12:44:29 -0800
> Larry McVoy <lm at bitmover.com> wrote:
> > Disks are much higher volume and are forced to be reliable "enough".
> That "enough" is the critical point. Check the average read failure
> rate of SATA drives. It is 1 per 10^14 bits for my ST3500320AS. The
recoverable read error rate I presume.
> drive has a capacity of 512 bytes/sect x 976773168 sectors. I.e. I will
> get at least one read error when I try to read the entire disk 25
> times. If I build a RAID out of 5 of this drives I only need 5 reads
> through the RAID to get a read error and the RAID will degrate.
> > If you aren't backing up with a crc then you are doing it wrong.
> With a CRC you can detect bit rott. (Probably. Somthing like MD5 or
> SHA-1 is mch better then a CRC.) But you can't repair the defect data.
> So you want ECC...
I plan to stick ZFS on my storage.
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