Re: feature suggestion to handle read errors during re-sync of raid5

[John Robinson <john.robinson@anonymous.org.uk>]

On 30/01/2010 17:51, Giovanni Tessore wrote:
> [...]  Having the OS
> recover and rewrite the sectors makes me feel back in the past, when 
> under DOS we used PCTools and other utilities to do this recovery stuff 
> on ST-506 drives .... and this works well on raid, but in sinlge disk 
> configuration, shouldn't these be data loss?
> 
> I'm confused... how much are modern disks reliable?

I think the problem is that modern discs haven't got more reliable, but 
they have got much, much bigger; "modern" 2G discs had a read error rate 
of 1 bit per 10^14, and current 2T discs have the same, so while on a 2G 
disc you could read the whole surface of the disc tens of thousands of 
times before being likely to get a read error, now it's only tens of 
times. Someone did recently post links to a formal article analysing 
this subject to this list, but I can't find it :-(

Cheers,

John.