[Beowulf] Re: ECC support on motherboards?

[Joel Jaeggli]

Robert G. Brown wrote:
> On Wed, 21 May 2008, Eugen Leitl wrote:
> 
>> On Wed, May 21, 2008 at 03:36:24PM +0100, Kozin, I (Igor) wrote:
>>>
>>>> b) Laptops.  I'd REALLY like a flash-driven laptop.
>>>
>>> Who wouldn't? But what's the typical lifespan of flash memory?
>>
>> Current SSDs claim >1 Mh MTBF, largely due to wear-leveling.
> 
> A Mh is, lessee, 100 years?  So one failure per hundred systems per
> year?  Or if it is truly due to wear, perhaps it is zero failures per
> hundred systems for 50 years, then an increasing failure rate out to
> 100+?
> 
> If it is wear, however, lifetimes may depend on usage, and using it as a
> root fs and/or home directory may significantly shorten lifetime.

given a 300,000 cycle rated life span, a solid wear-leveling algorithm, 
and a controller that groups and shadows incomplete writes you can write 
to a 16GB flash drive at 20MB/s for 9 years before it exceeding it's 
warranted cycle life.

It used to be fairly trivial to exercise a given block until it failed, 
but by in large that won't happen anymore.

>    rgb
> 
>>
>>
>