On Wed, Sep 05, 2012 at 10:34:24AM +0200, Sean Murray wrote:
> On 09/04/2012 09:21 PM, Konstantin Olchanski wrote:
> >On Sun, Sep 02, 2012 at 05:33:24PM -0700, Todd And Margo Chester wrote:
> >>
> >>Cherryville drives have a 1.2 million hour MTBF (mean time
> >>between failure) and a 5 year warranty.
> >>
> >
> >Note that MTBF of 1.2 Mhrs (137 years?!?) is the *vendor's estimate*.
>
> Its worse than that, if you read their docs, that number is based on an
> average write/read rate of (intel) 20G per day, which is painfully little
> for a server.
> 

I am not sure if I believe any of these numbers. Here is why.

I just checked my running systems and the oldest "/" filesystem on a USB Flash
drive is "Nov 2010", not quite 2 years old. (other USB Flash drives are probably
older than that but have "new" filesystems when upgraded from SL4 to SL5 to SL6).

USB Flash drives were never intended for heavy duty use as "/" disks,
the Linux ext3/ext4 is not even supposed to be easy on flash media,
and I remember the dire predictions of flash media "wear-out".

I read all this to mean that nobody knows how long flash media really lasts in production use.

I think "they" have to fix the sudden-death problem first, *then* we will start
seeing how the media life-time and wear-out comes into play.

-- 
Konstantin Olchanski
Data Acquisition Systems: The Bytes Must Flow!
Email: olchansk-at-triumf-dot-ca
Snail mail: 4004 Wesbrook Mall, TRIUMF, Vancouver, B.C., V6T 2A3, Canada